Release 10.1A: OpenEdge Data Management:
DataServer for ORACLE


ORACLE size limitations

The limitations that ORACLE and OpenEdge place on the number of columns or fields per table are important issues to consider when you plan a migration:

When you use the Progress-to-ORACLE utility to create an ORACLE database, it adds columns to an ORACLE table to accommodate Progress functionality (see Table 7–4). Because ORACLE limits the maximum number of columns, you must plan for the additional columns generated by the utility when you create the database schema.

When you design the OpenEdge database tables that you want to make compatible with ORACLE, leave enough columns free for the migration utility to use. Table 7–5 lists how many columns on an ORACLE table each Progress object requires.

Table 7–5: Columns required by Progress objects 
Database object
Number of columns
Record ID
One per table.
Array
One per array element.

Column names

ORACLE allows column names to be only 30 characters long. The Progress-to-ORACLE utility truncates the names of the Progress fields so that they meet this limitation. After running the utility, you can use the Data Dictionary to access the schema holder and modify the field name.

Column width

The Progress-to-ORACLE utility uses either a field’s format or width information (_width) value) when it defines the field as an ORACLE column. Since OpenEdge allows a field to hold more data than the field’s format will display, you can select Use Width Field to create a column that is wider than the format indicates. If a column generated by the utility is not wide enough to hold the data, the utility does not load the remainder of the data for that table into the ORACLE database.

Prior to running the utility, you need to determine which method of calculating column size will be used to ensure your data will fit. If necessary, use the Adjust Field Width tool in the Data Dictionary to enlarge character, decimal, and array fields or the database administration tool, DBTOOL. For more information on DBTOOL see OpenEdge Data Management: Database Administration .

Note: For those fields with a display format of x(8), the utility automatically generates a VARCHAR(30) column.

If you have miscalculated the width of a column, you can change it.

To change the width of the column:

  1. Use an editor to open the file with the .sql extension, which contains information for the entire database.
  2. Find the section of the file that describes the table.
  3. Assign the column a larger value to accommodate the data.
  4. Extract the section of the file that describes the table, including the delete table syntax, and place it in another file named filename.sql. Be sure to include any index information for the table.
  5. Re-create the table by running SQL*Plus. Enter the following command at the system prompt:
  6. sqlplus userID/password < filename.sql 
    

    This command deletes the data definition for the table and re-creates it.

  7. Load the data.

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