JPS62219124A - Item attribute genetic processing method in database - Google Patents

Abstract

PURPOSE:To execute automatically and selectively inheritance of a necessary attribute only by considering the inheritance conditions registered beforehand when a slave table is newly prepared from an existing data item. CONSTITUTION:In inheritance conditions memory parts 22A-22C of item attribute memory parts 21A-21C provided for respective data items, the inheritance conditions can be registered beforehand and by an inheritable attribute extracting part 15 and in item attribute inheritance information list preparing part 17, the inheritable attribute is continued. Thus, a user does not need re- define the item attribute each time a slave table 25 is generated. When the inheritance conditions are registered once correctly, the attribute is automatically continued, and therefore, the attribute input error at the time of re-definition is prevented.

Description

[Detailed Description of the Invention] [Summary] A data item attribute storage unit in a database. It is possible to define and store genetic conditions for each item attribute, and when a new child table is created from an existing data item, the previously registered genetic conditions are taken into account. To automatically and selectively inherit only necessary attributes for data item attributes. [Industrial Application Field] The present invention provides a database system having a function of generating a child table based on data extracted from a parent table of a database using specified search conditions. , relates to an item attribute genetic processing method in a database that performs inheritance of data item attributes. [Prior Art] Nine data items on a database are usually given nine different attributes. These attributes include, for example, data types such as numerical values, characters, and truth values, the number of digits of numerical values or characters, a semantic attribute such as the unit of data being time series data, and the range of possible values. By the way, in a database such as a so-called relational database, it is possible to save the results of a data search based on predetermined conditions as a new table, and to continue performing various operations on that table. Conventionally, in this type of database system, when creating a new child table based on a parent table, the data type among the data item attributes of the parent table is inherited by the item attributes of the child table, but other data items are inherited. General item attributes are not inherited. [Problems to be Solved by the Invention] According to the conventional method, attributes for data items are insufficiently handled, and from the search results of the a table. When creating a child table, only certain item attributes were inherited. Therefore, the user has to redefine the item attributes that are not inherited to the child table after the child table is generated, which poses a problem in that operations are complicated. However, if all item attributes are inherited unconditionally from the parent table to the child table. Also for attributes that are not required for the child table. In this case, too, a new problem arises in that the attributes must be redefined or the child table must be used only within a limited range. The present invention aims to solve the above problems by making it possible to set necessary genetic conditions for each data item in advance, so that when a child table is generated, desired item attributes are automatically inherited to the child table. The purpose is to provide a method. [Means for Solving the Problems] FIG. 1 shows an example of the basic configuration of the present invention. In FIG. 1, 10 is a keyboard terminal, 11 is a database operation command input from the keyboard terminal 10, 12 is a syntax analysis unit that performs syntax analysis of the command, and 13 is a syntax analysis tree that is the result of analysis by the syntax analysis unit 12. , 14 is a semantic analysis unit that checks and analyzes the meaning of the command, and 15 is a heritable attribute that checks the genetic conditions in child table generation for each item specified in the syntax analysis tree 13 and extracts heritable attributes. Extraction part, 1
6 is an item attribute genetic information list in which information regarding inherited item attributes is set; 17 is an item attribute genetic information list 1
6, an item attribute genetic information list creation section 18, a table definition section that defines the item attributes of the child table according to the item attribute genetic information list 16, and 19, a database operation section that performs reference and update processing for the database. 20 is a database; 21A to 21C are item attribute storage units that store item attributes of each data item; 22A to 22C are genetic condition storage units that store genetic conditions for child tables; 23 is a parent table that is a genetic source; 24A to 21C are 24G represents an item attribute storage unit for item attributes of child tables, and 25 represents a child table generated by search or the like. In the present invention, each item attribute storage section 21A of the parent table 23
~21C are provided with genetic condition storage units 22A~22C so that genetic conditions can be registered. This genetic condition is for each data item. (al attributes are all hereditary, (b) only the data type is hereditary; fc) genetic attribute selection is performed by an operation, etc. This is information regarding the attributes to be inherited by the data items of the newly generated child table 25. When defining the child table 25, the heritable attribute extraction unit 15 refers to the genetic condition storage units 22A to 22C and extracts only item attributes that satisfy the genetic condition. The item attribute genetic information list creation unit 17 is. A one-item attribute genetic information list 16 is created for the extracted item attributes. The item attribute genetic information list 16 has search item number information, pointer information to genetic light, and inherited attribute information. As a result, table definition part 1
8 are item attribute storage units 24A to 24C of the child table 25.
One item of attribute information can be set for . The item attribute storage units 24A to 24C are configured to have pointers to, for example, the item attribute storage units 21A to 21C of the parent table 23, and if the item attribute of the parent table 23 changes. The item attributes of the child table 25 are also automatically changed. [Operation] Generally, which attribute among the various attributes given to each data item in the parent table 23 should be inherited by the child table 25 depends on each data item. That is, the attributes to be inherited differ depending on the data item. According to the present invention, the genetic condition storage units 22A to 2 of the item attribute storage units 21A to 21C provided for each data item.
Genetic conditions can be registered in advance in 2C, and the heritable attributes are inherited by the heritable attribute extraction unit 15 and item attribute genetic information list creation unit 17. There is no need to redefine item attributes. Once genetic conditions are correctly registered, attributes are automatically inherited, thereby preventing attribute input errors during redefinition. [Example] Figure 2 shows an example of item attributes for detailed explanation of the present invention.
FIG. 3 shows an example of a database operation command, FIG. 4 shows an example of a syntax analysis tree, FIG. 5 shows an example of an item attribute genetic information list, and FIG. 6 shows a processing explanatory diagram of an embodiment of the present invention. The employee database includes items such as employee numbers and salary items for the employees. For example, as shown in FIG. 2(a),
The data type attribute is "numeric value", the 2-digit number attribute is "5 digits", and the attribute that can take values is r 10000~
99999 J, and various attributes such as "none" as the unit attribute are stored. Furthermore, in the case of the present invention, genetic condition information is set in the genetic condition storage section 22A. In this example, if the search conditions are other than calculations, all attributes are inherited as is, and "+" or "-" is inherited.
In the case of the operation ``'', the data type attribute and the unit attribute are inherited, and in the case of the operations ``*'' and ``/'', only the data type attribute is instructed to be inherited. Similarly, as shown in FIG. 2(b), genetic conditions are set in the genetic condition storage section 22B for salary items as well. Figure 3 is an example of a command to search the database, and rGET"J requests to obtain the employee number and the payment amount. In other words, a child consisting of the employee number and the payment amount. The table is required to be generated internally.The payment amount is defined by subtracting the income tax item value from the salary item value. rFROMJ allows the target parent table to be ” has been shown to be. Then, rWHEREJ specifies that the search condition, that is, the data to be retrieved as a child table is for an employee whose affiliation is "First Development." When a command 11 as shown in FIG. 3 is input, the syntax analysis unit I2 shown in FIG. 1 generates a syntax analysis tree 13 as shown in FIG. 4 by analyzing the syntax. Note that the generation of this syntax parse tree 13 is the same as the conventional method, so a detailed explanation will be omitted. The heritable attribute extraction unit 15 sequentially searches the search item list of the syntax analysis tree 13 shown in FIG. Retrieve an item and store the genetic condition storage unit 22 regarding that item.
With reference to A, etc., inheritable attributes are extracted. In this example, since the employee number is not related to the calculation, it can be seen from FIG. 2(a) that all attributes are heritable. Similarly, for salary items, Figure 2 (b)
, it can be seen that the data type attribute and the unit attribute are heritable. The item attribute genetic information list creation section 17 shown in FIG. 1 creates an item attribute genetic information list 16 as shown in FIG. 5 from the heritable attributes extracted by the heritable attribute extraction section 15. This item attribute genetic information list 1-16 includes search item number information, a pointer to the genetic source item, genetic information, and the like. From this item attribute genetic information list 16, the item attributes of the child table that is the search result can be automatically defined. FIG. 6 particularly shows an example of the processing of the heritable attribute extraction section 15 and the item attribute genetic information list creation section 17 shown in FIG. Numbers ■ to ■ in the following description correspond to process numbers ■ to ■ shown in FIG. (2) Determine whether processing has been completed for all items appearing in the search item list in the syntax analysis tree 13. ■ If processing has not finished, retrieve the search item from the search item list. First, the item 9, for example, employee number, will be retrieved. ■ Determine whether the search item is an arithmetic expression. If the search item is not an arithmetic expression, the secondary process (2) is skipped. ■ If the search item is an arithmetic expression, check the genetic condition of the item attribute related to the operation and extract the heritable attribute. ■ Determine whether a search item is used in a search condition. If it is not used in the search conditions, skip the first process (■). ■ Check the genetic conditions of item attributes related to the search items used in the search conditions and extract heritable attributes. ■ A one-item attribute genetic information list 16 is created from the extracted heritable attribute information. Next, control is returned to process (2), and the same process is repeated for the primary search item until the search item list is completed. [Effects of the Invention] As explained above, according to the present invention, necessary genetic conditions are set in advance for each data item. When a child table is generated, desired item attributes can be automatically inherited by the child table, eliminating the need for redefinition and improving operability. In particular, it facilitates the management of semantic information regarding data items in the database. For example, DSS (Decision 5uppo
rt System), handling of data item attributes such as time series attributes is important, and application of the present invention enables flexible handling of attributes.

[Brief explanation of drawings]

Figure 1 is an example of the basic configuration of the present invention, Figure 2 is an example of item attributes for detailed explanation of the present invention, Figure 3 is an example of a database operation command, Figure 4 is an example of a syntax analysis tree, FIG. 5 shows an example of an item attribute genetic information list, and FIG. 6 shows a processing explanatory diagram of an embodiment of the present invention. In the figure, 10 is a keyboard terminal and 11 is a command. 12 is a syntax analysis unit, and 13 is a syntax analysis tree. 14 is a semantic analysis section, and 15 is a heritable attribute extraction section. 16 is an item attribute genetic information list, 17 is an item attribute genetic information list creation unit, and 18 is a table definition unit. 19 is a database operation unit, and 20 is a database. 21A to 21C are item attribute storage units, 22A to 22C are genetic condition storage units, 23 is a parent table, 24A to 24C are item attribute storage units, and 25 is a child table. Patent Applicant: Fujitsu Co., Ltd. Representative Patent Attorney Hiroshi Mori 1) (1 other person) No. 412] Akino Nekin-Ryo Banquet No. 60

Claims (1)

[Claims] Based on the data extracted from the parent table (23) of the database according to specified search conditions, the child table (
25), a genetic condition storage means (22A, 2
2B,...), and when generating a child table based on the parent table of the database, the above genetic conditions set for each data item in the parent table are checked, and heritable attributes are extracted. means (15); and for each data item of the generated child table, attribute information including at least pointer information to the data item of the parent table serving as the genetic source and genetic information extracted by the extraction means (15). It is characterized by comprising an item attribute genetic information list creation means (17) for creating a list (16), and a means (18) for defining a child table based on the created item attribute genetic information list (16). An item attribute genetic processing method in a database.