JP7653766B2 - Table correction device and table correction program - Google Patents

Description

This disclosure relates to a table modification device that modifies a table having a column-oriented database data structure.

In fields dealing with big data and artificial intelligence (AI), there is a demand for efficient and fast handling of large volumes of data. A column-oriented database is a database architecture specialized for the aggregation and analysis of such large volumes of data. In a column-oriented database, multiple records to be registered in a table are stored in the database in columns. This allows efficient and fast access to processes that read specific column data, such as aggregation and analysis.

A conventional column-oriented database technology includes a method of dividing a plurality of records into columns, organizing the resulting blocks into one group, and managing the blocks (see, for example, Japanese Patent Laid-Open No. 2003-233663).
However, when making modifications such as adding or deleting columns to a table using this conventional technology, the necessary column data from the current table must be re-registered in the working table, which poses a problem of long processing time.

Japanese Patent Application Publication No. 11-154155

The present disclosure aims to provide a table modification device that can quickly modify tables that have a column-oriented database data structure.

The table correction device according to the present disclosure is
a receiving unit that receives correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generating unit that generates a temporary table that is a base for generating a second table, which is the first table after the modification instructed by the modification instruction information is reflected, and that is a table having the data structure of the column-oriented database;
and a block registration unit which determines, from among the blocks of the first table stored in one or more blocks, the blocks to be registered in the temporary table based on the modification instruction information, and registers the determined blocks in the temporary table.

The correction instruction information is
The modification indicates the addition of a column to the first table;
The block registration unit
An unregistered block is generated in the temporary table, the unregistered block being made up of one or more unregistered fields indicating cells whose data are unregistered.

The correction instruction information is
The modification indicates a column to be deleted from the first table;
The block registration unit
The blocks included in the column designated by the modification instruction information are determined, and the determined blocks are excluded from registration in the temporary table.

The correction instruction information is
the modification indicates a column of the first table whose attribute is to be changed and the attribute to be changed;
The block registration unit
The block belonging to the column for which the attribute change is instructed by the modification instruction information is determined, and the attribute of the area of the temporary table in which the determined block should be registered is set to the attribute instructed by the modification instruction information.

The table correction program according to the present disclosure is
On the computer,
a receiving process for receiving correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generation process for generating a temporary table that is a base for generating a second table, which is the first table after the modification instructed by the modification instruction information is reflected, and that is a table having the data structure of the column-oriented database;
Among the blocks of the first table stored in the state of one or more blocks, the blocks to be registered in the temporary table are determined based on the modification instruction information, and a block registration process is executed to register the determined blocks in the temporary table.

According to the present disclosure, the table modification device includes a block registration unit that registers data from the first table to the temporary table in blocks, thereby providing a table modification device that can quickly modify a table having a column-oriented database data structure.

FIG. 11 is a diagram showing a comparative example of the table correction device 100 according to the first embodiment. FIG. 2 is a diagram showing an outline of the operation of the table correction device 100 according to the first embodiment. FIG. 1 is a functional block diagram of a table correction device 100 according to a first embodiment. FIG. 1 is a diagram showing a hardware configuration of a table modifying device 100 according to a first embodiment. FIG. 11 is a diagram according to the first embodiment, showing table definition information 62a and a first table 70. FIG. 11 is a diagram of the first embodiment, showing the generation of a first table 70 having a data structure of a column-oriented database. FIG. 13 is a diagram according to the first embodiment, showing table entity management information 63a and a table entity 41a before a definition change corresponding to the table entity management information 63a. FIG. 10 is a flowchart illustrating the operation of the table correction device 100 according to the first embodiment. FIG. 6 is a diagram according to the first embodiment, showing table definition change information 61 by an SQL statement for the first table 70 in FIG. 5 . FIG. 10 is a diagram showing table definition information 62b when table definition change information 61 is in the upper part of FIG. 9 in the diagram of the first embodiment. FIG. 11 is a diagram according to the first embodiment, showing table generation conditions 64 when table definition change information 61 indicates the addition of a column. FIG. 11 is a diagram of the first embodiment, showing a state in which the control unit 20 registers data of the table entity 41a before a definition change in a temporary table 90 in block units. FIG. 10 is a diagram showing table definition information 62b when table definition change information 61 is in the middle part of FIG. 9 in the diagram of the first embodiment. FIG. 11 is a diagram according to the first embodiment, showing table generation conditions 64 when table definition change information 61 indicates deletion of a column. FIG. 13 is a diagram in the first embodiment showing a state in which the block registration unit 920b registers data of the table entity 41a before a definition change in the temporary table 90 in block units. FIG. 10 is a diagram showing table definition information 62b when table definition change information 61 is as shown in FIG. 9 in the first embodiment. FIG. 11 is a diagram according to the first embodiment, showing table generation conditions 64 when table definition change information 61 is a change in a column attribute. FIG. 13 is a diagram in the first embodiment showing a state in which the block registration unit 920b registers data of the table entity 41a before a definition change in the temporary table 90 in block units.

The following describes the embodiments with reference to the drawings. Note that in each drawing, the same or corresponding parts are given the same reference numerals. In the description of the embodiments, the description of the same or corresponding parts will be omitted or simplified as appropriate.

Embodiment 1.
A table correction device 100 according to a first embodiment will be described with reference to FIGS.

In the following explanation, the table before modification is referred to as the first table, and the modified first table is referred to as the second table. The table that is the basis of the second table is referred to as the temporary table.

In the following explanation, table definition information 62 and table entity management information 63 will appear. The table definition information 62 and table entity management information 63 corresponding to the first table will be written as table definition information 62a and table entity management information 63a, and the table definition information 62 and table entity management information 63 corresponding to the modified second table 2 will be written as table definition information 62b and table entity management information 63b, distinguished by a and b.

In the following explanation, a table entity corresponding to the first table before the definition change and a table entity corresponding to the second table after the definition change will appear. The table entity corresponding to the first table will be referred to as table entity 41a before the definition change, and the table entity corresponding to the second table will be referred to as table entity 41b after the definition change, and will be distinguished by a and b.

Table modification device 100 is a device for modifying a table. Specifically, table modification device 100 performs at least one of the following modifications on a first table that has a plurality of columns and a plurality of rows, in which cell data is registered in cells formed by the intersections of the columns and the rows, and that is created with the data structure of a column-oriented database: adding a column, deleting a column, or changing the attributes of a column.

Fig. 1 shows a comparative example for clarifying the characteristics of table modification device 100 of embodiment 1. The comparative example will be described with reference to Fig. 1. In the comparative example, when a modification such as adding or deleting a column is made to the first table, the following processes (1) to (5) are carried out.
(1) In the comparative example, a new table is generated that is the basis for the second table, with a column added or deleted.
(2) In the comparative example, the current first table is searched to extract records that are rows.
(3) In the comparative example, the extracted records are loaded into a new table that has been created.
(4) In the comparative example, the first table is deleted.
(5) In the comparative example, the new table name is changed to the table name of the first table, and the new table is generated as the second table.

In the method of the comparative example, the search in (2) above is used to extract the required columns record by record and load them into a new table, which takes a lot of time. In particular, if the first table is compressed, the data increases due to data expansion during record conversion, and the data is loaded again into the new table and compressed, which takes even more time.

Figure 2 shows an outline of the operation of the table modification device 100 of the first embodiment in comparison with Figure 1. The table modification device 100 replaces the table by copying the data of the first table to a new table while keeping the data structure of the column-oriented database intact. For example, when adding a column to the first table, the table modification device 100 performs the following processes (1) to (5) on the first table.
(1) The table modification device 100 generates a temporary table, which is a new table to which a column has been added and which is to be the basis of the second table.
(2) Table modification device 100 copies the column block of the first table to a temporary table.
(3) The table modifying device 100 generates an empty block for the column to be added.
(4) The table modifying device 100 deletes the first table.
(5) The table modification device 100 changes the name of the temporary table to the name of the first table, and generates the temporary table as a second table.

The table modification device 100 eliminates the need to retrieve records one by one from the first table by searching, and copies data to a temporary table while retaining the blocks of the database structure of the first table, allowing the first table to be modified in a short time. In particular, since decompression and record conversion are not required even for compressed tables, time can be significantly reduced and processing can be accelerated. The table modification device 100 is described in detail below.

***Configuration Description***
3 is a functional block diagram showing the functional configuration of the table modification device 100. The table modification device 100 includes a reception unit 10, a control unit 20, a table generation condition determination unit 30, a table storage area 40, and an output unit 50. The table storage area 40 stores a table entity 41a before the definition is changed, that is, the entity of the first table, and a table entity 41b after the definition is changed, that is, the entity of the second table. The reception unit 10 is a reception unit 910. The control unit 20 is a temporary table generation unit 920A and a data registration unit 920B. The functions of the reception unit 10 to the output unit 50 will be described in the description of the operation. In the following description, the reception unit 10 may be referred to as the reception unit 910, and the control unit 20 may be referred to as the temporary table generation unit 920a or the block registration unit 920b.

Figure 4 shows the hardware configuration of the table modification device 100. The hardware configuration of the table modification device 100 will be explained with reference to Figure 4.

The table modification device 100 is a computer. The table modification device 100 includes a processor 110. In addition to the processor 110, the table modification device 100 includes other hardware such as a main memory device 120, an auxiliary memory device 130, an input IF 140, an output IF 150, and a communication IF 160. The processor 110 is connected to the other hardware via a signal line 170 and controls the other hardware.

The table modification device 100 has, as its functional elements, a reception unit 10, a control unit 20, and a table generation condition determination unit 30. The functions of the reception unit 10, the control unit 20, and the table generation condition determination unit 30 are realized by a table modification program 101.

The processor 110 is a device that executes the table modification program 101. The processor 110 is an integrated circuit (IC) that performs arithmetic processing. Specific examples of the processor 110 include a central processing unit (CPU), a digital signal processor (DSP), and a graphics processing unit (GPU).

The main memory 120 is a memory device. Specific examples of the main memory 120 are SRAM (Static Random Access Memory) and DRAM (Dynamic Random Access Memory). The main memory 120 holds the results of calculations by the processor 110.

The auxiliary storage device 130 is a storage device that stores data in a non-volatile manner. A specific example of the auxiliary storage device 130 is a HDD (Hard Disk Drive). The auxiliary storage device 130 stores a table modification program 101. The auxiliary storage device 130 realizes the table storage area 40. The auxiliary storage device 130 also stores information such as table definition change information 61, table definition information 62a, table definition information 62b, table entity management information 63a, table entity management information 63b, and table generation conditions 64.

The input IF 140 is a port through which data is input from each device. A keyboard 141 is connected to the input IF 140. The keyboard 141 is an example of an input device for inputting information. The output IF 150 is a port to which various devices are connected and through which the processor 110 outputs data to the various devices. A display device 151 is connected to the output IF 150. The communication IF 160 is a communication port through which the processor communicates with other devices.

The processor 110 loads the table modification program 101 from the auxiliary storage device 130 into the main storage device 120, and reads and executes the table modification program 101 from the main storage device 120.

The table correction program 101 is a program that causes a computer to execute each process, procedure, or step of the receiving unit 910, the temporary table generating unit 920a, and the block registration unit 920b, where the "part" in each of these units is interpreted as a "process," "procedure," or "step."

The table correction program 101 may be provided by being stored on a computer-readable recording medium, or may be provided as a program product.

5 to 7, a first table created as a column-oriented database will be described.
5 shows the table definition information 62a and a first table 70 generated based on the table definition information 62a. The table definition information 62a uses SQL. The first table 70 is created with a column-oriented database data structure. The first table 70 has columns corresponding to "ID,""salesdate,""branchname,""productname," and "sales" shown in the table definition information 62a.

Fig. 6 shows the generation of a first table 70 having a data structure of a column-oriented database. The data structure of a column-oriented database will be described with reference to Fig. 6. The input data shown in the upper right is data such as a CSV file. The input data has column items of ID, sales date, branch name, product name, and sales, and corresponds to Fig. 5. Each row of the input data is a record. Records with input data IDs of 10001 to 1003 make up group #1. Records with input data IDs of 10004 to 1005 make up group #2. Group #1 is blocked by the control unit 20 as follows:
As block B#1, IDs 1001, 1002, and 1003 are blocked. As block B#2, sales dates 2019.5.30, 2019.5.31, and 2019.5.31 are blocked. As block B#3, branch names Tokyo, Osaka, and Yokohama are blocked. As block B#4, product names Refrigerator, Air Conditioner, and Television are blocked. As block B#5, sales 15, 30, and 20 are blocked. Group #2 is also blocked by the control unit 20 in the same way as group #1. The explanation of blocking of group #2 is omitted. As shown in FIG. 6, a table entity 41a before the definition change of the first table for the input data is generated for each group in the database. The table entity 41a before the definition change and the table entity 41b after the definition change shown in the table storage area 40 in FIG. 3 are the table entities shown in FIG. 6.

The column-oriented database in Figure 6 has a table entity, which is table information having the data structure of a column-oriented database. A table entity is made up of one or more groups. A group is made up of one or more blocks. A block is made up of one or more fields.

<Table entity management information 63a>
Fig. 7 shows table entity management information 63a and a table entity 41a before a definition change corresponding to the table entity management information 63a. The table entity 41a before a definition change in Fig. 7 is the table entity 41a before a definition change shown in Fig. 6. The table entity 41a before a definition change and the table entity 41b after a definition change are recorded in the table storage area 40 of the auxiliary storage device 130. The table entity management information 63a that manages the table entity holds information on the block position and block size of the table entity. The table entity management information 63a is stored in the auxiliary storage device 130 and is managed by the control unit 20.

*** Operation Description ***
8 is a flow chart for explaining the operation of the table modifying device 100. The operation of the table modifying device 100 will be explained with reference to FIG.

<Step S1>
In step S1, the receiving unit 910 receives the table definition change information 61. The table definition change information 61 is modification instruction information.
The table definition change information 61 is modification instruction information that instructs modification of a first table shown in Fig. 6 described later, which has a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to the data structure of a column-oriented database. The table definition change information 61 is input by an input device such as a keyboard.

Figure 9 shows three examples of table definition change information 61 by SQL statements for the first table 70 in Figure 5. The top row is table definition change information 61 that instructs adding a column "Manufacturer". The middle row is table definition change information 61 that instructs deleting a column "Sales". The bottom row is table definition change information 61 that instructs changing the data type, which is an attribute of the column "Sales Date", from DATE to TIMESTAMP. Note that in Figure 9, each of the modification instructions for adding a column, deleting a column, and changing a column attribute is received separately, but the table definition change information 61 may include any two of them or all three.

<Step S2: Adding a column>
The following description will be given on the assumption that the table definition change information 61 indicates the addition of the column in the upper part of FIG.
In step S2, the temporary table generating unit 920a generates the temporary table 90.
The temporary table 90 is a table that is used to generate a second table, which is a modified first table reflecting the modifications instructed by the table definition change information 61, which is modification instruction information, and has a column-oriented database data structure. The temporary table generation unit 920a refers to the received table definition change information 61 and modifies the table definition information 62a.
10 shows table definition information 62b when the table definition change information 61 is in the upper part of FIG. 9. In the table definition information 62b, "manufacturer varchar (20)" has been added. In step S2, the temporary table generating unit 920a refers to the table definition information 62b, defines the table whose table definition information has been changed as a temporary table 90, and generates the temporary table 90.

<Step S3>
FIG. 11 shows table generation conditions 64 when the table definition change information 61 is for adding a column.
In step S3, in the case of adding a column, the table generation condition determination unit 30 determines a table generation condition 64 in Fig. 11 from the table definition information 62b in Fig. 10 and the table entity management information 63a in Fig. 7. The table generation condition 64 shown in Fig. 11 consists of an execution order, a block input source which is information specifying a block of the first table, a block output destination which indicates an output position to a temporary table, and an action which indicates the processing content of adding a column, deleting a column, or changing an attribute of a column.
Fig. 12 shows a state where the block registration unit 920b registers the data of the table entity 41a before the definition of the first table is changed in units of blocks in the temporary table 90 in accordance with the table generation condition 64 of Fig. 11 determined by the table generation condition determination unit 30. The contents of Fig. 12 will be described in step S5.

<Step S4>
In step S4, the block registration unit 920b determines whether the table entity 41a before the definition change has one or more groups. If there is no group, the process proceeds to step S7. If there is one or more groups, the process proceeds to step S5. If multiple groups exist in the table entity 41a before the definition change, the control unit 20 processes each group. In other words, when processing the next group, the process returns from step S6 to step S4.

<Step S5>
In step S5, the block registration unit 920b determines which blocks of the first table, which are stored in one or more blocks, should be registered in the temporary table based on the table definition change information 61, which is modification instruction information, and registers the determined blocks in the temporary table.
The table definition change information 61 indicates the addition of a column to the first table as a modification. In this case, the block registration unit 920b generates an unregistered block in the temporary table, which is made up of one or more unregistered fields indicating cells in which data is not registered. A specific description is given below.
The block registration unit 920b reorganizes each group. Reorganization means adding a column to each group if the table definition change information 61 is adding a column, deleting a column from each group if the table definition change information 61 is deleting a column, and changing the attribute of the column in each group if the table definition change information 61 is changing the attribute of the column. The block registration unit 920b copies blocks to be copied from the table entity 41a before the definition change to the temporary table 90 in group units for group #1 according to the table generation condition 64 in FIG. 11, as shown in FIG. 12. In addition, the block registration unit 920b generates an additional block B#6 having "NULL" for the column to be added, executes group reorganization, and adds it to the temporary table 90. For group #2, the block registration unit 920b also performs the same process in the loop of steps S4, S5, and S6.

<Step S7>
In step S7, the block registration unit 920b changes the name of the temporary table 90 in which the block is registered. That is, the block registration unit 920b changes the name of the temporary table 90 in FIG.

<Step S8>
In step S8, the output unit 50 outputs the second table in the format of the first table 70 shown in FIG. 5 as a result of the change in the table definition, and the process ends.

<Delete column>
Next, a case where the table definition change information 61 instructs the deletion of a column will be described.

<Step S1>
In step S1, the receiving unit 910 receives the table definition change information 61 shown in the middle part of FIG.

<Step S2>
In step S2, the temporary table generating unit 920a refers to the received table definition change information 61 and changes the table definition information 62a.
Fig. 13 shows table definition information 62b when the table definition change information 61 is in the middle section of Fig. 9. In the table definition information 62b, "Sales" has been deleted from the table definition information 62a in Fig. 5. In step S2, the control unit 20 refers to the table definition information 62b, defines the table whose table definition information has been changed as a temporary table 90, and generates the temporary table 90.

<Step S3>
FIG. 14 shows table generation conditions 64 when the table definition change information 61 is for deleting a column.
In step S3, the table generation condition determination unit 30 determines the table generation condition 64 in Fig. 14 from the table definition information 62b in Fig. 13 and the table entity management information 63a in Fig. 7. The table generation condition 64 shown in Fig. 14 is the same as that in Fig. 11, so a description thereof will be omitted.
FIG. 15 shows a state in which the block registration unit 920b registers the data of the table entity 41a before the definition of the first table is changed in the temporary table 90 in block units in accordance with the table generation condition 64 in FIG.

<Step S4>
The process in step S4 is the same as that in the case of adding a column.

<Step S5>
The table definition change information 61 indicates, as a correction, a column to be deleted from the first table. In this case, the block registration unit 920b determines the blocks contained in the column indicated in the table definition change information 61, and excludes the determined blocks from registration in the temporary table. A specific description will be given below.
In step S5, the block registration unit 920b reorganizes each group. In accordance with the table generation conditions 64 in FIG. 14, the block registration unit 920b copies blocks to be copied from the table entity 41a before the definition change to the temporary table 90 in group units as shown in FIG. 15 for group #1. Since block #5 of the table entity 41a before the definition change is to be deleted according to the table generation conditions 64 in FIG. 14, the block registration unit 920b does not copy block #5. As shown in FIG. 15, block B#5 in the table entity 41a before the definition change is not copied, so the "Sales" column is deleted.

<Steps S7 and S8>
The following steps S7 and S8 are similar to the case of adding a column, and therefore the explanation will be omitted.

<Column attribute change>
Next, a case where the table definition change information 61 instructs a change in the attribute of a column will be described.

<Step S1>
In step S1, the reception unit 10 receives the table definition change information 61 shown in the lower part of FIG.

<Step S2>
In step S2, the temporary table generating unit 920a refers to the received table definition change information 61 and changes the table definition information 62a.
Figure 16 shows table definition information 62b when the table definition change information 61 is in the middle section of Figure 9. In the table definition information 62b, the data attribute of "sales date" is set to timestamp compared to the table definition information 62a in Figure 5. In step S2, the temporary table generation unit 920a refers to the table definition information 62b, defines the table whose table definition information has been changed as a temporary table 90, and generates the temporary table 90.
The temporary table is described below.

<Step S3>
FIG. 17 shows table generation conditions 64 when the table definition change information 61 is a change to a column attribute .
In step S3, the table generation condition determination unit 30 determines the table generation condition 64 of Fig. 17 from the table definition information 62b of Fig. 16 and the table entity management information 63a of Fig. 7. The table generation condition 64 shown in Fig. 17 is the same as that of Fig. 11, so a description thereof will be omitted.
FIG. 18 shows a state in which the block registration unit 920b registers the data of the table entity 41a before the definition of the first table is changed in the temporary table 90 in block units in accordance with the table generation condition 64 in FIG.

<Step S4>
The process in step S4 is the same as that in the case of adding a column.

<Step S5>
The table definition change information 61 indicates the column of the first table whose attribute should be changed and the attribute to be changed as the modification. In this case, the block registration unit 920b determines the block belonging to the column whose attribute is instructed to be changed by the table definition change information 61, and sets the attribute of the area of the temporary table in which the determined block should be registered to the attribute instructed by the modification instruction information. A specific description will be given below.
In step S5, the block registration unit 920b reorganizes each group. In accordance with the table generation condition 64 in Fig. 17, the block registration unit 920b copies blocks to be copied from the table entity 41a before the definition change to the temporary table 90 in group units as shown in Fig. 18 for group #1. Since the attribute of block #2 of the table entity 41a before the definition change is subject to conversion to timestamp in the table generation condition 64 in Fig. 17, the block registration unit 920b converts the data format of block #2 to imestamp type and copies it to the temporary table 90.

<Steps S7 and S8>
The following steps S7 and S8 are similar to the case of adding a column, and therefore the explanation will be omitted.

***Advantages of First Embodiment***
According to the table modification device 100, it is not necessary to retrieve records one by one from the first table by searching, but data is copied to the temporary table while retaining the blocks of the database structure of the first table, thereby enabling modification of the first table in a short time.
In particular, since decompression and record conversion are not required even for compressed tables, time can be significantly reduced and processing speed can be increased.

In the first embodiment, data migration from the table entity 41a before the definition change to the first table was performed by copying the data, but it may also be performed by cutting the data.

When adding a column using the table definition change information 61, the table modification device 100 may generate a new block depending on the attributes of the column to be added, such as the data type, compression attribute, encryption attribute, or a combination thereof.

When adding a column using the table definition change information 61, the table modification device 100 may generate an additional block with the column value previously specified by the user as the default value.

When changing column attributes using table definition change information 61, the table modification device 100 may convert data in blocks held by the table entity 41a before the definition change according to the attributes to be changed, such as data type, compression attribute, encryption attribute, or a combination thereof, and generate blocks for a temporary table.

100 table modification device, 10 reception unit, 20 control unit, 30 table generation condition determination unit, 40 table storage area, 41a table entity before definition change, 41b table entity after definition change, 50 output unit, 61 table definition change information, 62 table definition information, 63a table entity management information, 63b table entity management information, 64 table generation condition, 70 first table, 90 temporary table, 110 processor, 120 main memory device, 130 auxiliary memory device, 140 input IF, 150 output IF, 160 communication IF, 170 signal line, 910 receiving unit, 920a temporary table generation unit, 920b block registration unit.

Claims (4)

a receiving unit that receives correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generating unit that generates a temporary table having the data structure of the column-oriented database, the temporary table being a base for generating a second table, which is the first table after the modification specified by the modification instruction information is reflected, and that modifies table definition information defining the first table by referring to the modification instruction information;
a table generation condition determination unit that determines table generation conditions for generating the second table based on the changed table definition information and table entity management information that holds block positions and block sizes of the first table;
a block registration unit that registers, in the temporary table, blocks to be registered in the temporary table, among the blocks of the first table stored in a state of one or more blocks, based on the determined table generation condition,
The correction instruction information is
The modification indicates the addition of a column to the first table;
The table generation condition determination unit
In response to the modification instruction information instructing the addition of a column to the first table as the modification, by referring to the changed table definition information and the table entity management information holding the block position and block size of the first table,
determining that the block to be registered in the temporary table in the first table is an input source block;
determining that the destination block in the temporary table of the source block is the destination block;
A decision to copy an action of registering from the first table to the temporary table from the input source block to the output destination block;
determining, as an output destination block, a block in the temporary table corresponding to the column to be added to the first table by the modification instruction information;
A decision to generate an empty block with no data (NULL) as an action for the destination block corresponding to the column to be added to the first table;
In addition,
determining the table creation conditions, which indicate the blocks to be registered in the temporary table and the empty blocks to be created in the temporary table, by reflecting each of the decisions ;
The block registration unit
A table modification device that generates an unregistered block consisting of one or more unregistered fields indicating cells in which data is not registered as the empty block in the temporary table by referring to the action indicating the generation of the empty block in the determined table generation conditions for adding the column to the first table. a receiving unit that receives correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generating unit that generates a temporary table having the data structure of the column-oriented database, the temporary table being a base for generating a second table, which is the first table after the modification specified by the modification instruction information is reflected, and that modifies table definition information defining the first table by referring to the modification instruction information;
a table generation condition determination unit that determines table generation conditions for generating the second table based on the changed table definition information and table entity management information that holds block positions and block sizes of the first table;
a block registration unit that registers, in the temporary table, blocks to be registered in the temporary table, among the blocks of the first table stored in a state of one or more blocks, based on the determined table generation condition,
The correction instruction information is
The modification indicates a column to be deleted from the first table;
The table generation condition determination unit
In response to the modification instruction information indicating, as the modification, a column to be deleted from the first table, by referring to the changed table definition information and the table entity management information holding the block position and block size of the first table,
determining that a block in the first table is a source block;
determining, as an output destination block, a block of the output destination in the temporary table other than the input source block corresponding to the column to be deleted among the input source blocks;
A decision to copy the action of the source block to the destination block;
A decision to perform an action on the temporary table for the source block corresponding to the column to be deleted as a no-operation (NOP) that does not copy the source block;
In addition,
determining the table generation conditions in which the blocks to be registered in the temporary table and deleted blocks of the first table that are not to be registered in the temporary table are indicated by reflecting the respective decisions ;
The block registration unit
A table modification device that, when deleting the column present in the first table, determines that the input source block indicated by the no operation (NOP) in the table generation conditions is the deleted block, and excludes the determined deleted block from registration in the temporary table. a receiving unit that receives correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generating unit that generates a temporary table having the data structure of the column-oriented database, the temporary table being a base for generating a second table, which is the first table after the modification specified by the modification instruction information is reflected, and that modifies table definition information defining the first table by referring to the modification instruction information;
a table generation condition determination unit that determines table generation conditions for generating the second table based on the changed table definition information and table entity management information that holds block positions and block sizes of the first table;
a block registration unit that registers, in the temporary table, blocks to be registered in the temporary table, among the blocks of the first table stored in a state of one or more blocks, based on the determined table generation condition,
The correction instruction information is
the modification indicates a column of the first table whose attribute is to be changed and the attribute to be changed;
The table generation condition determination unit
by referring to the table definition information that has been changed and the table entity management information that holds the block position and block size of the first table, in response to the modification instruction information indicating, as the modification, the column of the first table whose attribute should be changed and the attribute whose attribute should be changed,
determining that a block in the first table is a source block;
determining that the destination block in the temporary table of the source block is the destination block;
determining that the action is to copy from the source blocks other than the source block corresponding to the column of the first table whose attribute is to be changed to the destination block;
determining that an action from the source block to the destination block corresponding to the column of the first table whose attribute is to be changed is a data conversion;
In addition,
By reflecting each of the decisions, the table generation condition is determined, which indicates the blocks to be registered in the temporary table, the attribute conversion blocks in which the attributes of the blocks in the first table should be converted, and the action of converting the attributes;
The block registration unit
a table modification device that determines the attribute conversion block indicated by the table generation conditions, and sets the attribute of an area of the temporary table in which the determined attribute conversion block is to be registered to the attribute indicated by the table generation conditions. On the computer,
a receiving process for receiving correction instruction information instructing a correction to a first table having a plurality of columns and a plurality of rows, with cell data registered in cells formed at the intersections of the columns and the rows, and in which one or more cell data in the same column are blocked and stored in one or more blocks according to a data structure of a column-oriented database;
a temporary table generation process for generating a temporary table that is a table that is a base for generating a second table, which is the first table after the modification instructed by the modification instruction information, and that is a table having the data structure of the column-oriented database, and for modifying table definition information that defines the first table by referring to the modification instruction information;
a table generation condition determination process for determining table generation conditions for generating the second table based on the changed table definition information and table entity management information holding the block positions and block sizes of the first table;
a block registration process for registering, in the temporary table, blocks to be registered in the temporary table, among the blocks of the first table stored in a state of one or more blocks, based on the determined table generation condition,
The correction instruction information is
The modification indicates the addition of a column to the first table;
In the table generation condition determination process,
In response to the modification instruction information instructing the addition of a column to the first table as the modification, by referring to the changed table definition information and the table entity management information holding the block position and block size of the first table,
determining that the block to be registered in the temporary table in the first table is an input source block;
determining that the destination block in the temporary table of the source block is the destination block;
A decision to copy an action of registering from the first table to the temporary table from the input source block to the output destination block;
determining, as an output destination block, a block in the temporary table corresponding to the column to be added to the first table by the modification instruction information;
A decision to generate an empty block with no data (NULL) as an action for the destination block corresponding to the column to be added to the first table;
In addition,
determining the table creation conditions , which indicate the blocks to be registered in the temporary table and the empty blocks to be created in the temporary table, by reflecting each of the decisions ;
In the block registration process ,
A table modification program that generates an unregistered block consisting of one or more unregistered fields indicating cells in which data is not registered as the empty block in the temporary table by referring to the action indicating the generation of the empty block in the determined table generation conditions for adding the column to the first table .

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