SQL/MX 3.2.1 Management Manual (H06.26+, J06.15+)

Dropping SPJs
For more information about and examples of dropping SPJs, see the SQL/MX Guide to Stored
Procedures in Java.
Dropping SQL/MX Tables
To remove a table and its dependent objects from the database, use the DROP TABLE statement.
Use the PURGEDATA utility to remove only the data from a table and its dependent objects and
leave the objects intact.
For more information, see the SQL/MX Reference Manual.
Dropping SQL/MX Tables and Their Data
To drop a table and its data, use the DROP TABLE statement. Dropping a base table with
dependencies is essentially dropping each of the dependent objects (indexes, constraints) separately.
SQL drops all the dependencies automatically.
If the table contains references to another object (for example, an RI constraint), the drop operation
fails if RESTRICT is specified. The drop operation should succeed if you use the CASCADE option
to drop these dependent objects.
Guidelines for Dropping an SQL/MX Table and its Data
• If you plan to use the TMF subsystem to recover an SQL/MX table, see “Recovering Tables”
(page 240).
• To have the authority to drop a table, you must have all the security and authority required to
drop or invalidate all dependent objects, including access to all the catalogs describing all
the dependent objects.
• You can use the DROP TABLE statement to drop a table with partitions, but not to drop individual
partitions within a table. For more information about using the MODIFY utility to drop the
individual partitions of a table, see “Dropping Partitions for SQL/MX Tables and Indexes”
(page 172).
• When you drop a table, the operation invalidates the programs that depend on that table.
To avoid expensive automatic recompilations of these programs, you should change them as
necessary and recompile them explicitly, as in “Steps for Dropping an SQL/MX Table and its
Data” (page 175).
• A table that has an active DDL lock (one for which the process that created it still exists) cannot
be dropped even if you specify CASCADE. An active DDL lock will be released when the
utility locking the file completes.
• If you specify RESTRICT and table is referenced by a view, a trigger, or a referential constraint
of another table, or if the table has an active DDL lock, the specified table cannot be dropped.
• If you specify CASCADE, the table and all of its views, triggers, referential constraints, and
inactive DDL locks are dropped.
For more information, see the SQL/MX Reference Manual.
Steps for Dropping an SQL/MX Table and its Data
1. Start an MXCI session. Enter a LOG command to initiate a log file for statements and commands
entered in this session. Keep the log for your records.
2. Determine the name of the table you want to drop.
3. Enter the DROP TABLE statement.
4. Revise the application source code as needed to reflect your changes to the database. Process
and compile the updated source file. For more information, see the SQL/MX Programming
Manual for C and COBOL.
Dropping Objects From an SQL/MX Database 175