skip to main content
OpenEdge Data Management: DataServer for ODBC
The DataServer Tutorial : Verifying a schema holder
 

Verifying a schema holder

The Verify Table Definition utility allows you to verify that the schema holder for your ODBC data source matches the data definitions in the data source. For example, if you delete the Customer table from the data source but not from the schema holder, this utility reports that the schema holder contains an orphaned object. You can verify the schema information in a single table or from multiple tables, and then choose to update the tables so that the schema information matches the data-source definitions.
The Verify utility reads the definitions in the ODBC data source and compares them to the information in the schema holder. It reports the differences that it finds and their degree of severity. These are the categories of differences and how they impact your database applications:
*Minor — These differences have no impact on the usability of your application.
*Retained — These differences cannot be corrected by the Update/Add utility, hence the term "retained." You must determine how severely they impact your application and change the data definitions either in the schema holder using the Data Dictionary or in the data source.
*Severe — These differences might cause your application to malfunction. When the Verify utility detects severe differences, it automatically updates the schema holder to solve the discrepancies by adjusting the schema-image information in the schema holder to match the data-source definitions. Severe differences in definitions that the DataServer uses internally also cause the schema holder to be updated.
The following table lists the differences that this utility detects.
Table 25. Verify utility report
Database object
Difference
Category
Table
Description
Retained
Table
Foreign type
Severe
Table
Name in OpenEdge
Retained
Table
Package name
Severe
Table
ROWID index
Retained
Index
Active
Minor
Index
Description
Retained
Index
Name in OpenEdge
Retained
Index
Unique
Retained1
Index field
Abbreviated
Minor
Index field
Ascending
Severe
Index field
Order
Severe
Field
Case sensitivity
Retained
Field
Decimals
Retained2
Field
Description
Retained
Field
Extent
Severe
Field
Initial value
Retained3
Field
Mandatory
Retained
Field
Name in OpenEdge
Retained
Field
Order
Retained
Field
OpenEdge data type
Retained4
Field
OpenEdge format
Retained5
Field
Shadow-column Name
Severe
1 When you update an index, it is flagged as unique if it was defined as unique in the ODBC data source or the schema holder.

2 If the corresponding information in the ODBC data source is incompatible with the information in the schema holder, the affected fields are not updated. For example, if the data-source data type is decimal and the OpenEdge data type is CHARACTER, the data-type information is not updated.

3 If the corresponding information in the ODBC data source is incompatible with the information in the schema holder, the affected fields are not updated. For example, if the data-source data type is decimal and the OpenEdge data type is CHARACTER, the data-type information is not updated.

4 If the corresponding information in the ODBC data source is incompatible with the information in the schema holder, the affected fields are not updated. For example, if the data-source data type is decimal and the OpenEdge data type is CHARACTER, the data-type information is not updated.

5 If the corresponding information in the ODBC data source is incompatible with the information in the schema holder, the affected fields are not updated. For example, if the data-source data type is decimal and the OpenEdge data type is CHARACTER, the data-type information is not updated.

To verify a table:
1. Access the Data Administration tool, if you are not already there, and select DataServer > ODBC Utilities > Verify Table Definition. The Pre-Selection Criteria For Schema Pull dialog box appears:
Note: The Owner field in the Pre-Selection Criteria dialog is labeled Collection/Library when the foreign DBMS type is DB2/400.
2. Type preselection criteria values into the fields if desired. These values preselect the data-source objects that the utility uses to update the schema holder. By default, the wild card symbol (*) appears; it specifies that the utility uses all of the objects in the data source.
3. By default, the utility verifies objects in the schema holder that match objects in the ODBC data source. To check whether there are objects in the data source that are not represented in the schema holder, deselect the Verify only objects that currently exist in the schema holder toggle box.
4. Select Output differences to file if you anticipate a large volume of differences, or wish to save the report. There is a 32K limit on the contents of the verify report. The file that is produced will be named, <ldbname>+.vfy and will be written to the working directory.
5. Click OK. A dialog box lists the objects and table information that you preselected. For example:
6. Select the objects that you want to verify, then click OK.
7. To select tables by matching a pattern, click Select Some. The Select Objects by Pattern Matchdialog box appears:
8. Type the pattern that you want to match, then click OK to start the verification. If you did not choose to output the differences to a file, dialog boxes that list the objects and the verification results appear:
9. When reading the text of the report, SH indicates the value in the schema image; NS indicates the value in the ODBC database:
10. Click Close to return to the Schema Verify dialog box.
The utility automatically selects objects with severe differences for updating. You can select or deselect all other objects as you wish. Note that you must resolve retained differences manually. Retained differences appear in subsequent reports until you resolve them.
11. Click OK to start the update or Cancel to quit the utility without updating the schema holder.