Annotation: Information support of IP. Extra-machine information support. Basic concepts of information classification. Concepts and basic requirements for information coding system. The composition and content of design operations of classifiers. Documentation system. Machine information support. Design of screen forms of electronic documents. Information base and methods of its organization.
It is a means to solve the following problems:
- unambiguous and economical presentation of information in the system (based on encoding of objects);
- organization of procedures for the analysis and processing of information, taking into account the nature of relations between objects (based on the classification of objects);
- organization of user interaction with the system (based on screen data input-output forms);
- ensuring the effective use of information in the control loop of activity of the automation object (based on a unified documentation systems).
IP Information Support includes two complexes: in-machine information support (classifiers of technical and economic information, documents, methodological instructional materials) and in-machine information support (layouts / screen forms for inputting primary data into a computer or outputting output information, structure information base: input, output files, database).
The following general requirements are imposed on information support:
- information support should be sufficient to support all the automated functions of the facility;
- for coding information, classifiers adopted by the customer should be used;
- for encoding input and output informationwhich is used at the highest level of management, classifiers of this level should be used;
- compatibility with information support of systems interacting with the developed system should be ensured;
- document forms must meet the requirements of the customer’s corporate standards (or unified documentation systems);
- the structure of documents and screen forms should correspond to the characteristics of terminals at workplaces of end users;
- formation schedules and content informational messages, as well as the abbreviations used should be generally accepted in this subject area and agreed with the customer;
- iP should include means for controlling input and output information, updating data in information arrays, integrity control information base, protection against unauthorized access.
IP Information Support can be defined as a combination of a single classification systemsunified documentation systems and information base [ 9.1 ] .
Extra-machine information support
Basic concepts of classification of technical and economic information
In order to ensure effective search, computer processing and transmission of technical and economic information via communication channels, it must be presented in digital form. For this purpose, it must first be ordered (classified), and then formalized (encoded) using a classifier.
Classification - this separation of many objects into subsets according to their similarity or difference in accordance with accepted methods. Classification captures regular relationships between classes of objects. An object is understood to mean any object, process, phenomenon of a material or intangible property. Classification system allows you to group objects and highlight certain classes that will be characterized by a number of common properties. Thus, the set of rules for the distribution of set objects on subsets is called classification system .
A property or characteristic of a classification object that allows you to establish its similarity or difference with other classification objects is called a sign classification. For example, the sign “the role of the partner enterprise in relation to the activities of the automation object” allows us to divide all enterprises into two groups (into two subsets): “suppliers” and “consumers”. A set or subset combining a part of classification objects according to one or several criteria is called classification grouping.
A classifier is a document with the help of which a formalized description of information in an information system is carried out, containing the names of objects, the names of classification groups and their code symbols [9.1].
By scope of action, the following types are distinguished classifiers: international, state-wide (system-wide), industry and local classifiers.
International classifiers are part of the System of International Economic Standards (SIEC) and are required for the transfer of information between organizations of different countries of the world community.
National (system-wide) classifiers are mandatory for organizing the processes of transmission and processing of information between state-level economic systems within a country.
Industry classifiers are used to perform information processing procedures and transfer it between organizations within the industry.
Local classifiers are used within individual enterprises.
Each classification system characterized by the following properties:
- system flexibility;
- system capacity;
- degree of system occupancy.
System flexibility - this is the ability to allow the inclusion of new features, objects without destroying the structure of the classifier. The necessary flexibility is determined by the lifetime of the system.
System capacity - this is the largest number of classification groups allowed in this classification system.
System occupancy rate defined as the quotient of dividing the actual number of groupings by the amount of system capacity.
Currently, two types are most commonly used. classification systems: hierarchical and multidimensional.
When using the hierarchical classification method, "consistent separation of many objects into subordinate, dependent classification groups "[9.2]. The classification scheme obtained on the basis of this process has a hierarchical structure. In it, the initial volume of classified objects is divided into subsets according to some criterion and is detailed at each next classification level. Generalized image of the hierarchical classification scheme presented in fig. 9.1.
Fig. 9.1.
The characteristic features of the hierarchical system are:
- the ability to use an unlimited number of classification features;
- the subordination of classification features, which is expressed by dividing each classification group formed by one attribute into many classification groups according to a lower (subordinate) basis.
Thus, classification schemes built on the basis of the hierarchical principle have unlimited capacity, the value of which depends on the depth of classification (the number of stages of division) and the number of classification objects that can be located at each stage. The number of objects at each classification level is determined by the base of the code, that is, the number of characters in the selected code alphabet. (For example, if the alphabet is two-digit decimal numbers, then 100 objects can be placed on the same level). The choice of the necessary classification depth and code structure depends on the nature of the classification objects and the nature of the tasks for which it is intended
The concept and components of information support
IO - a set of design decisions on the volume, structure and storage of information. IO is intended to reflect information characterizing the state of the managed object, and is the basis for making management decisions.
IO is divided into:
Intra-machine - information fund (input. Primary, operational, reference, result and other files), automated databases (local, network, multi-user databases, database management systems);
Extra-machine - systems of indicators, documentation and workflow, classification and coding of information.
Characteristics of extra-machine information support
Extra-machine information support includes: a system for classifying and coding information; management documentation systems; system of organization, storage, modification of documentation.
The extra-machine information base is a collection of messages, signals and documents in the form perceived by a person directly without the use of computer technology.
In the non-machine sphere, in the management process, the exchange of information is realized in the form of a movement of documents between the managed and managing systems: documents containing the planned information (orders, instructions, planned tasks, schedules, etc.) follow from the control body to the object; on the feedback line - from the object to the management body - documents containing accounting and reporting information (information about the current or past state of the control object) follow. Extra-machine information support allows identification of the control object, formalize information, present data in the form of documents.
Characteristics of machine information support. The concept of DB, DBMS.
Intra-machine information support contains data arrays that form the information base of the system on machine carriers, as well as a system of programs for organizing, accumulating, maintaining and accessing information of these arrays, intra-machine information fund (input. Primary, operational, normative-reference, result and other files) Automated databases (local, network, multi-user databases, database management systems);
The database is a set of independent materials presented in an objective form (articles, calculations, normative acts, court decisions and other similar materials), systematized in such a way that these materials can be found and processed using an electronic computer
DBMS - This is a special program or a set of programs with which you can administer or monitor any data. In fact, DBMSs are designed to manipulate data. DBMSs can be: network, hierarchical, relational - it all depends on the type of database.
Description of the stages of development of the database.
Infological Design
The main tasks of infological design are to determine the domain of the system and form a view of the software from the perspective of the community of future database users, i.e. infological model of software.
The infological model of software is a description of the structure and dynamics of software, the nature of the information needs of users in terms that are understandable to the user and not dependent on the implementation of the database. This description is expressed in terms of not individual software objects and the relationships between them, but of their types, associated integrity constraints and those processes that lead to the transition of the subject area from one state to another.
Logical database design
At the stage of logical design, a logical database structure is developed corresponding to the logical software model. The solution to this problem depends significantly on the data model supported by the selected DBMS.
The result of this stage is the database schema of the conceptual and external levels of architecture, compiled in the data definition languages \u200b\u200b(DDL, Data Definition Language) supported by this DBMS.
Physical database design
The stage of physical design consists in linking the logical structure of the database and the physical storage environment in order to most efficiently place data, i.e. mapping the logical structure of the database into the storage structure. The issue of placing the stored data in the memory space, the choice of effective methods of access to the various components of the "physical" database. The results of this step are documented in the form of a storage scheme in a data definition language (DDL). Decisions made at this stage have a decisive influence on system performance.
Key concepts of a relational data model
The relational data model - developed by E. Codd in 1970. A logical data model that describes:
Data structures in the form of (time-varying) sets of relationships;
Set-theoretic operations on data: union, intersection, difference and Cartesian product;
Special relational operations: selection, projection, connection and division; and
Special rules to ensure data integrity.
Attribute - in databases - the name or structure of a record field. An attribute characterizes the size or type of information contained in a field.
A domain - in databases - is the set of all attribute values \u200b\u200bin some respects.
Record - in relational databases - a row of a data table consisting of fields of various types.
A relationship key is a relationship attribute that uniquely identifies each of its tuples. A composite key consists of several attributes.
Relation - a two-dimensional table containing some data. Rows of such tables correspond to records, and columns to attributes.
Relational algebra is a formal relationship manipulation system whose main operations are: projection, connection, intersection and union.
Database structure - the principle or procedure for organizing records in the database and the relationships between them.
Relational algebra Constraint, join, and intersection operations
Projection
The projection of a relation R over the attributes R1, R1, R1 ... Rn, where each attribute belongs to R, is a relation with a heading (R1, R2, R3 ... Rn) and a body containing many tuples of the form (r1, r2, r3, ... rn). In this case, duplicate tuples are deleted.
The projection is called a vertical slice of the relationship.
Syntax R
Union
The union of two compatible relationships is called a relation with the same heading as R1 and R2, and a body that includes all tuples of operands, except for repeating ones.
Syntax R1 union R2
Intersection
Syntax
Subtraction
Syntax R1 minus R2
Cartesian product
The Cartesian product of two relations R1 (R11, R12, R13 ...) and R2 (R21, R22, R23, ...) is the relation whose heading is grip headerrelations R1 and R2:
(R11, R12, R13 ... R21, R22, R23, ...), and the body consists of tuples, which are the linkage of tuples of relations R1 and R2
(r11, r12, r13 ... r21, r22, r23 ....) such that (r11, r12, r13 ...) belongs to R1, and (r21, r22, r23 ...) belongs to R2 /
Syntax R1 times R2
Compound
Usually consider several varieties of the join operation.
General join operation
Q connection
Equi Connection
Natural compound
General join operation:
By joining the relations R1 and R2, the condition refers to the relation (R1 times R2) where C, where C is a logical expression that can include attributes of the relations R1 and R2 and / or scalar expressions.
Q connection
(R1 times R2) where R11QR21 - Q-connection of the relation R1 by the attribute R11 with the relation R2 by the attribute R21. Record and
Equi Connection
Natural compound
Let the relations R1 (R11, R12, R13, .. R1n, Z1, Z2, ... Zn) and R2 (Z1, Z2, ... Zn, R21, R22, R23, .., R2m) be given. Then the natural connection of the relations R1 and R2 is the relation with the heading (R11, R12, R13, .. R1n, Z1, Z2, ... Zn, R21, R22, R23, .., R2m) and a body containing many tuples (r11, r12 , r13, ... r1n, z1, z2, z3, ... zn, r21, r22, ... r2m) such that (r11, r12, r13, ... r1n, z1, z2, z3, ... zn) belongs to R1, and (z1 , z2, z3, ... zn, r21, r22, ... r2m) belongs to R2
Syntax
Division
Syntax R1 divideby R2
DBMS Functions
1. Data management directly in the database
2. Data management in computer memory (data caching)
The DBMS works with a large database; when buffering, the user receives only part of the database necessary for his specific task
3. Transaction Management
A transaction is an indivisible sequence of data manipulation operators (insert, delete, read, etc.) from the point of view of actions on the database.
The transaction is performed in RAM. If it is successful, then the DBMS makes a corresponding change to the disk. Otherwise, the changes do not affect the state of the database.
4. Support for database languages
5. Management of changes in the database and logging (logging). This function provides reliable data storage and the ability to restore the state of the database in emergency situations. A record is made in the change log (transaction log) before the manipulations. To restore the database after a failure, a protocol (log) and an archive copy of the database are used (a full copy of the database by the time the protocol is filled).
DBMS components
1. data and metadata - contain system tables, user tables, field names, procedures, etc.
2. Memory unit:
File block controlling the location of files on disk
A buffer block that buffers data from main memory
3) Query compiler - processes a call to the DBMS
5) Data Modification - Data Modification Requests
6) Modification of the scheme - requests to change the structure of the database, tables, views
7) Data Scheme - the entire set of tables
8) Transaction block - is responsible for the integrity of the system, interacts with the query compiler and the memory block.
DBMS classification
DBMS classification
| Classification sign | DBMS Type | Key features |
| By the number of users | 1 - user | At a particular moment in time, 1 user is working with the database |
| Multi-user workgroup database | Number of users less than 50 people | |
| Multiuser enterprise database | Number of users over 50 | |
| By database location | Centralized | DB on one machine |
| Distributed | The database is distributed in a computer network | |
| According to the data model | Network CODASYL (CODASYL Conference on DAta SYstems Language - Conference on languages \u200b\u200bof data processing systems) - an organization (the name is pronounced “kodasil”) that took an active part in the evolution of information technology in the 60-80s of the XX century. Founded in 1959 to develop a standard programming language, this language is called COBOL. The conference is currently disbanded) Hierarchical IMS Relational Multidimensional Object Oriented | |
| By method of application and scope of use | Transactional (operational) OLTP - systems (On line transaction processing) | The DBMS works with a database in which the minimum time is allocated for transactions. Database queries should be displayed as soon as possible. |
| Data storage OLAP system (On line analytical processing) | DBMS works with a database designed to obtain the necessary information in the development of strategic or tactical decisions. To perform information analysis. | |
| Architecture | Client server | The server provides the basic functions of the DBMS, the client - supports the user interface with the server |
SQL Command Types
Types of Language Commands
Ddl- data definition language
CREATE TABLE, ALTER TABLE, DROP TABLE, CREATE VIEW, ALTER VIEW, DROP VIEW, CREATE INDEX, DROP INDEX
DML - data manipulation language
INSERT, UPDATE, DELETE
DQL - Data Query Language
DCL - data management language, or data administration commands
CREATE DATABASE, ALTER DATABASE, DROP DATABASE, GRANT (granting access rights for actions on specified database objects), REVOKE (depriving access rights for actions on specified database objects), etc.
Data Administration Commandsprovide the ability to audit and analyze operations within the database. Can be used to analyze the performance of the data system as a whole.
START AUDIT, STOP AUDIT
Transaction Management Commands -allow the processing of information integrated into a transaction
COMMIT, ROLLBACK, SAVE POINT, SET TRANSACTION (Transaction Name Assignment)
Procedural language
DECLARE, OPEN, FETCH, CLOSE, EXECUTE, etc.
19. SQL data types. SQL Functions.
Data types
Some of the most common built-in functions:
| ABS * | calculates the absolute value of a number |
| Acos | calculates arccosine |
| Asin | calculates arcsine |
| ATAN | calculates arc tangent |
| CEILING | rounds up |
| Cos | calculates the cosine of an angle |
| Cot | returns the cotangent of an angle |
| DEGREES | converts an angle value from radians to degrees |
| EXP | returns to the exponent |
| FLOOR | rounds down |
| LOG * | calculates the natural logarithm |
| LOG10 | calculates the decimal logarithm |
| PI | returns the value pi |
| Power | exponentially |
| RADIANS | Converts angle value from degree to radians |
| Rand | will return a random number |
| ROUND * | performs rounding with a given accuracy |
| Sign | defines the sign of a number |
| SIN * | calculates the sine of an angle |
| Square | squares a number |
| SQRT * | extracts the square root |
| Tan | returns the tangent of an angle |
| Ascii | returns the ASCII code of the left character of a string |
| Char | ASCII code returns the character |
| CHARINDEX | defines the serial number of the character from which the substring begins to enter the string |
| DIFFERENCE | returns string match |
| LEFT * | returns the specified number of characters from the beginning of the line |
| Len * | returns string length |
| LOWER * | converts all characters of a string to lowercase |
| LTRIM * | removes spaces at the beginning of a line |
| Nchar | returns Unicode character by code |
| PATINDEX | searches for a substring in a string according to the specified pattern |
| REPLACE | replaces substring occurrences with the specified value |
| QUOTENAME | converts a string to Unicode format |
| REPLICATE | replicates a string a specific number of times |
| REVERSE | returns a string whose characters are written in reverse order |
| RIGHT | returns the specified number of characters from the end of the string |
| Rtrim | removes spaces at the end of a line |
| SPACE | returns the specified number of spaces |
| STR | converts a numeric type value to character format |
| Stuff | deletes the specified number of characters, replacing with a new substring |
| SUBSTRING | returns a substring of the specified length for the string from the specified character |
| Unicode | returns the unicode code of the left character of a string |
| UPPER | converts all characters of a string to uppercase |
Limitation
Projection
Union
Intersection
The intersection of two compatible relations of type R1 and R2 is a relation with the same heading as that of relations R1 and R2, and a body consisting of tuples belonging to both relations R1 and R2 at the same time.
Syntax
Subtraction
Subtracting two relations of the type R1 and R2 compatible by type is a relation with the same heading as the relations R1 and R2 and a body consisting of tuples belonging to the relation R1 and not belonging to R2.
Syntax R1 minus R2
Cartesian product
The power of a product is equal to the product of capacities. If the attributes R1 and R2 have attributes with the same name, then before performing the Cartesian product operation, such attributes must be renamed. Type compatibility not required.
What exams should be taken by students who have completed the academic year R1 [semester<=2*курс]R2
Equi Connection this compound when Q is equality.
Natural compound
The connection is made according to the same attributes.
Division
The division operation has two operands binary and unary. The resulting relation consists of single-attribute tuples, including the values \u200b\u200bof the first attribute of the tuples of the first operand-relation, such that the set of values \u200b\u200bof the second attribute coincides with the set of values \u200b\u200bof the only attribute of the second operand-relation.
Syntax R1 divideby R2
Concept and components of an information system
The information system (IS) as a whole is an automated system designed to organize, store, replenish, support and present information to users in accordance with their requests.
The information system has two components: software and electronic information storage.
1. Information support - the totality of a single system of classification and coding of information, unified documentation systems, schemes of information flows circulating in the organization, as well as a methodology for building databases.
The purpose of the information support subsystem is the timely formation and delivery of reliable information for making management decisions.
2. Technical support - a set of technical means intended for the operation of an information system, as well as the relevant documentation for these means and technological processes
3. Mathematical and software - a set of mathematical methods, models, algorithms and programs for implementing the goals and objectives of the information system, as well as the normal functioning of a complex of technical means.
4. Organizational support - a set of methods and means governing the interaction of workers with technical means and among themselves in the process of developing and operating an information system.
5. Legal support - a set of legal norms that determine the creation, legal status and functioning of information systems that govern the procedure for obtaining, converting and using information.
Lecture 4
Information support of information systems
The concept of information support and its structure.
Extra-machine information support.
Machine information support.
The concept of information support and its structure
The concept of "Information Support" appeared in the 1970s. in connection with the introduction of computers in the practice of processing economic problems and with the creation of automated control systems (ACS). The structure of the information system was developed, suggesting its division into non-machine (system of indicators, classifiers and codes, documentation, information flows) and intramachine (information arrays (files) in computer memory and on computer media).
Information support (IO) is an important component of automated information systems and is directly related to the organizational structure of the object and the functional subsystems of IP.
Information Support is intended to reflect information characterizing the state of the managed facility; serves as the basis for management decisions.
There are several approaches to the structuring of economic information, one of which is logical - it allows you to establish structural elements depending on the functional purpose of the information and its features.
Consider the functional purpose and role of various structural elements in automated processing.
The lowest level information unit is requisitesfrom which more complex information structures are formed. Details reflect the individual properties of the object, include a combination of numbers or letters that have semantic content and are not amenable to further division. Literal information can be represented in the form of code symbols (for example, unit code). In machine processing, the synonyms of the concept of “props” are “field”, “element”, “attribute”, details are not unique in their content and are divided into attributes and base details. Attributes signs characterize the quality side of the object, and base details - quantitative. For example, the name of the unit and its code are used as the attribute attribute, and the basis information is the number of employees. Each document includes any number of requisites-attributes and requisites-bases.
Indicator - a logical statement containing the qualitative and quantitative characteristics of the displayed phenomenon.
The indicator is the minimum informational composition for the formation of an independent document. Documents usually contain a large number of indicators. Even in one line, several indicators of different structure can be distinguished. When organizing a database, indicators as units of information form its content. Each indicator has many values \u200b\u200band is calculated according to its own algorithm. Scorecarddefines the content of management documents and arrays. For example, the system of economic indicators presented in the balance sheet of the enterprise, in the order for piece-rate wages, etc.
The scorecard is also set depending on the level of management: corporation, concern, firm, enterprise, organization, unit.
The set of indicators contained in the document forms informational message.
A group of homogeneous documents united by a certain characteristic (for example, a reporting period) is information array (file). A file is the basic structural unit in automated processing. Information is recorded in the PC memory by files, where files of constant and variable information are allocated. Arrays according to various criteria can be combined into streams used in solving various sets of control problems. The relation of information to a particular management function gives reason to highlight the complex structure of information as information subsystem. Information system covers all the information of an economic object and is a structural unit of the highest level.
Thus, information support includes the totality of a single system of indicators, information flows - options for organizing workflow; classification systems and coding of economic information, a unified documentation system and various information arrays (files) stored in the machine and on computer media and with varying degrees of organization.
Information support (IO) is an important component of automated information systems and is directly related to the organizational structure of the object and the functional subsystems of IP.
Information support is intended to reflect information characterizing the state of the managed facility; serves as the basis for management decisions.
The basis of information support is information. In the theory of machine processing, information is considered in relation to the technology of its transformation for control purposes, i.e. as a set of information that is the object of collection, transmission, storage and processing. Information can be recorded in documents and on computer media; is the subject and means of labor.
As a means of labor, information acts on the control object in order to develop management decisions. As a subject of labor, information is the basis for building information technology.
The structure of economic information is quite complex and includes various combinations of information structures having a hierarchical structure. In fig. 3.1 is an example of a hierarchical construction of an information system.
Fig. 3.1. The structure of economic information |
The logical approach to the structuring of economic information made it possible to distinguish the following structural units depending on their functional purpose: props, indicator, document, information message, information array (file), information subsystem and information system. Consider the functional purpose and role of various structural elements in automated processing.
The information units of the lower level are the details and indicators that serve as the basis for the compilation of documents and storage in the machine's memory.
Props - the simplest unit, consists of signs - numbers and letters that have semantic meaning and are not amenable to further division. Requisites are ambiguous in their purpose and are divided into attribute attributes reflecting the qualitative side of the object, for example, the name of the material, and base details reflecting the quantity line of the object, for example, amount of material, amount, volume, length, etc.
Each attribute is characterized by its names and meanings, for example:
| Names of Props Props |
| > |
| V |
| Attributes signs |
| Base details |
Details-attributes are subject to logical processing (sorting, grouping, searching), details-bases - to arithmetic processing. The combination of one base and all the attributes related to it forms an indicator - a logical statement containing the qualitative and quantitative characteristics of the reflected phenomenon.
Based on this definition, it can be seen that in the above example, two indicators are reflected.
Each indicator has many values \u200b\u200band is calculated according to its own algorithm.
A document is a composite unit of information, including many details and giving certain quantitative and qualitative (or only qualitative) characteristics of an object, process, phenomenon.
Each economic task is characterized by certain forms of documents and the system of indicators contained in them.
The document is reflected on paper. Further, in the machine’s memory, all homogeneous documents (information messages) are formed into an information file — the main structural unit for storing information in the computer’s memory during automated processing of economic tasks.
Information files have a different functionality. So, files of conditionally constant, variable, input, intermediate, result, archive and other information are distinguished. Some files are used only for processing one task, others for several tasks. As a rule, a large number of information files are involved in the automated processing of an economic task.
For example, when processing financial transactions related to cash settlement, information files are created for the chart of accounts, directories of accountable persons, incoming cash orders and other documents, on the basis of which consolidated reporting is generated: cash book, journal order No. 1, etc.
The set of various information files used to process a complex of economic tasks (for example, accounting for cash transactions) organizes the next, rather complex, structural unit of information - the information flow.
As a rule, the creation of IP provides for the automated processing of economic tasks of various functional subsystems. For example, in the functional subsystem "Accounting" automated financial and settlement operations, accounting of labor and wages, accounting of inventory materials, accounting of fixed assets, production accounting, consolidated reporting, which allows you to highlight the information subsystem "Accounting".
The allocation of information subsystems in IP depends on the type of activity of the object.
So, for example, in the IS of enterprises and organizations, the functional subsystem “Accounting” is distinguished; in the bank’s IP - “Bank’s operational day”.
The totality of all the information subsystems of an object is a structural unit of information of the highest level - an information system that implements various management functions.
The creation of information systems and information technologies requires the organization and allocation of a special subsystem - information support.
The basis of information support is a system of indicators of the subject area. For example, in accounting, a system of indicators is determined by various areas of accounting, financial reporting; in banking, indicator systems are associated with cash management services for legal entities, credit, deposit and foreign exchange transactions, private deposits, etc.
The concept of "Information Support" appeared in the 1970s. in connection with the introduction of computers in the practice of processing economic problems and with the creation of automated control systems (ACS). The structure of the IO was developed, suggesting the division of IO into extra-machine (system of indicators, classifiers and codes, documentation, information flows) and intrafine (information arrays (files) in computer memory and on computer media).
In terms of the use of personal computers for processing economic problems, the continuity of previously developed principles for the creation of AI remains, but the guideline is made on the following:
Organization of the workstation and active user participation in the computing process (decentralized processing);
Automatic generation of primary documents by a personal computer (paperless technology);
Network integrated processing of complexes of economic tasks of an enterprise (organization);
Creation of a distributed database of the organization;
Extensive information and reference services to users;
Electronic document management;
Email, Internet access.
We can assume that the division of information support into extramachine and intramachine is very conditional, since modern automated technology for processing economic tasks is based mainly on information files located in the memory of the computer information system. Computer automatically creates primary documents, while paper input is constantly reduced. The workflow takes on an automated form; the route of their movement is set by the machine program.
The structure of information support includes:
The system of indicators of the subject area (for example, indicators of accounting, financial and credit activity, etc.);
Classification and coding systems of economic information;
Unified documentation system created manually or automatically;
Information flows using various options for organizing electronic document management;
Information arrays (files) stored in a machine on machine media having various degrees of organization (data bank) and subject to automated processing.
The purpose of information support is as follows.
1. Ensuring the organization of the presentation of information to users for their professional tasks in the preparation of management decisions, as well as the creation of working conditions for automated information technologies.
2. Ensuring mutual coordination of the tasks of functional subsystems on the basis of a unique formalized description of their inputs and outputs at the level of indicators and documents.
3. Creation of an effective organization of data storage and retrieval, which allows generating data for solving regulated tasks, as well as functioning in a mode of information and reference services.
The composition of information support is determined at the stage of IP design with the active participation of users.
The basis of its development is the analysis of the information systems of the economic object, during which the composition of the documentation used, the contents of the database, and the information links of the complexes of economic tasks are determined. A significant role in the creation of IO is given to the results of the statement of the problem, during the development of which users determine the specific composition of primary and summary documents, present their structure, methods of their preparation, etc. (see chap. 2).
AI design is carried out in close connection with automated processing technology and software.
Information support (IO) - the most important supporting subsystem of AIS - is designed to provide users with information characterizing the state of the managed facility and is the basis for making management decisions. AI is a combination of means and methods of constructing the information system of an economic object.Information support can be divided into extra-machine and intra-machine.
Extra-machine IO is a system of indicators, classifiers, codes and documentation.
Intra-machine IOs are various files on machine media, automated data banks (ABDs).
The design of IO, carried out jointly with users of AIS, is carried out from system positions in parallel with the design of technological, software and mathematical software.
During the design of IO, the following works are carried out: determining the composition of indicators necessary to solve economic problems, their space-time characteristics and information connections; the study of the possibilities of using national and industry classifiers, the development of local classifiers and codes; designing forms of new primary documents and identifying the possibilities of using a unified documentation system; determination of the type of organization of an automated data bank (DBA); designing forms of output of the resulting information.
The aim of the implementation of AIS is to further informatize the end user, therefore, his participation in ongoing information and implementation work is necessary and is an important prerequisite for their successful implementation. Additional features appear: maintaining directories in the PC,
the formation of various reports and arbitrary tables, a wide exchange of information between users, etc.
When processing economic data and compiling various summaries, there is a need for a grouping by attribute details. Grouping is based on classification and coding systems.
The classification consists in the distribution of the elements of the set into subsets based on the dependencies within the attributes. For example, when coding goods, classification attributes such as group, subgroup, variety (article), size are distinguished. The nomenclature of goods is an ordered complete list of homogeneous names, including individual lines - positions.
The Unified Classification and Coding System (ESCC) includes a wide variety of classifiers: National, designed for information exchange between different AIS, are developed in a centralized manner. Examples are classifiers of products, administrative-territorial division of the country, industries, professions, enterprises and organizations, units of measure, documentation, taxpayers, etc. Sectoral, common for individual industries, such as bank codes of charts of accounts, types of payments and deductions from wages, types of operations for moving material assets, etc.
Local, compiled for AIS enterprises and organizations, such as codes of structural units, personnel numbers of employees, debtors and creditors, etc.
Each item of the All-Russian Product Classifier (OKP), effective from July 1, 1994, contains a six-digit digital code, of which five characters represent the product group, and the sixth character represents the control number. The first two characters indicate product classes, the next character is a subclass, then a group is indicated with one character, the next character is a subgroup, and the last character is a product type.
For example:
5714309 - sawn facing slabs made of natural stone.
Two classification methods are distinguished: Hierarchical method - between classification groups, relations of submission are established, sequential detailing of type properties: class - subclass - group - subgroup - type, etc. In a hierarchical classification, each object falls into only one classification grouping; the union of groupings of one hierarchical level gives the initial set of objects. The depth of the hierarchy is determined by classification features. Facet method - the initial set of objects is divided into subsets in accordance with the values \u200b\u200bof individual facets. Facet - a set of values \u200b\u200bof one classification attribute. Facets are mutually independent. Each object can simultaneously be included in different classification groups.
The rules for constructing a hierarchical classifier are as follows: Determine the number of features, indicate their name and subordination (for example, A (material group) includes B (subgroup), B includes C (view), C includes G (subspecies)). Determine the number of values \u200b\u200bof each characteristic and select the maximum. Build a classification tree (Fig. 4.1).
4.
Fig. 4.2
For example, the designation 6431 means:
6 - forest species;
4 - sawn wood;
3 - edged sawn timber;
1 - the size of the workpiece.
If there is no hierarchical dependence between the features, then there is a single-level multi-valued (facet) classification. It is used to divide objects into classes in which the rank of all attributes is the same. Facet classes are obtained by assigning objects to classes according to attribute values \u200b\u200bat the same time. For example, many workers can be divided according to a number of signs: workshop, site, place of residence, gender, full name, salary, month. By grouping these signs, you can get answers to various questions. For example, which of the assembly shop workers earned more than 20 thousand rubles. per month?
The next step after the classification is coding or the process of assigning new symbols to various items of items according to certain rules established by the coding system. An example of a code mark is an identified taxpayer number that includes ten characters; the first and second signs indicate the territory, the third and fourth - the number of the state tax inspection, the rest - the taxpayer number and control category. The machine stores the directory of employees, including the last name, first name, patronymic, personnel number, position, salary, etc. During processing, the personnel number selects all the necessary background information and is printed in the output sheets.
Codes can be: digital, alphabetic, mixed. The following requirements are imposed on codes: they must cover all the nomenclatures by which the grouping is done; be the same for different tasks within one economic object; should be stable, often not reviewed; have a reserve in case new items appear; be economical, i.e. have a minimum value.
Code is a universal way of displaying information in the form of a system of correspondences between message elements and signals, by which these elements can be fixed. The final sequence of characters of the coding alphabet is called a code word (code combination) if it uniquely corresponds to any element of the set of messages, and the set of code combinations forms a code. The number of characters in a code combination is called the length
the words. As code symbols, various notations are used in the form of letters, numbers and special characters. The number of different values \u200b\u200bthat any character in a code can take is called code base.
The purpose of the codes is to ensure the grouping of information, the calculation of results by grouping signs and their printing in the output sheets. Codes are necessary for the convenience of information retrieval, storage and retrieval, its transmission through communication channels.
The most widely used coding systems: serial, serial, positional and combined.
The ordinal coding system assumes the assignment to all positions of the encoded nomenclature of ordinal numbers without omissions. For example, months are encoded in a calendar sequence: 01 - January, 02 - February, 03 - March, etc.
The serial system is focused on coding objects that are pre-grouped in a series. Series are assigned numbers according to their possible extensions. For example, a group of main workshops - code 01 to 03; group of auxiliary workshops - codes from 05 to 10, etc.
The positional coding system reflects the hierarchical subordination of classification features. In accounting, positional two- and three-digit codes are common. In the codes of accounts, an additional, analytical level is allocated to obtain more detailed information. For example, for account 70 “Payroll personnel,” there are two levels: for departments and for personnel numbers. For account 10 “Materials” there are three levels: type of material assets (1 character), warehouse (1 character) and item number (2 characters). The code structure is shown in Fig. 4.3. 
The widespread use of computer technology, including in warehouses, at retail enterprises, required the marking of goods with codes read by the machine. The most reliable method of reading a barcode was a hand-held laser scanner.
The bar code accurately and unambiguously defines each specific product, i.e. by the bar code you can find the product and its characteristics stored in the database of the trading system. In Russia, as in other European countries, the EAN-13 standard barcode is used. It includes 13 digits:
the first three (460) mean that the goods were produced in Russia;
four digits - this is the code of the company that produced this product;
five digits - product code;
one digit is a checksum calculated automatically by a certain formula over previous digits.
The standard set for bar coding includes: a printer for marking goods in stock; electronic scales with integrated label printing or
an additional printer on the packaging of weighted goods; cash registers with barcode scanners in the trading floor; mobile terminal in stock for goods accounting.
The use of bar coding leads to a reduction in losses on
shoplifting; tracking the availability of goods in a warehouse; mobile price management; organizing electronic (paperless accounting).
