The ALTER TABLE PROCEDURE data description statement modifies the definition of a table procedure in the dictionary. It is also a CA IDMS extension of the SQL standard. Using the ALTER TABLE PROCEDURE statement, you can:
To issue an ALTER TABLE PROCEDURE statement, you must own or hold the ALTER privilege on the table procedure named in the statement.
►►─── ALTER TABLE PROCEDURE ─┬────────────────┬─ table-procedure-identifier ──► └─ schema-name. ─┘ ►─┬─ ADD parameter-definition ────────────────────────────┬──────────────────►◄ │ ┌────────── , ───────────┐ │ ├─ ADD ( ─▼─ parameter-definition ─┴─ ) ────────────────┤ ├─ EXTERNAL NAME external-routine-name ─────────────────┤ ├──ESTIMATED ROWS row-count ────────────────────────────┤ ├──ESTIMATED IOS io-count ──────────────────────────────┤ ├──LOCAL WORK AREA local-stge-size ─────────────────────┤ ├──GLOBAL WORK AREA global-stge-size ─┬────────────────┬┤ │ └─ KEY ┬ key-ID ┬┘│ │ └─ NULL .┘ │ ├──USER MODE ───────────────────────────────────────────┤ ├──SYSTEM MODE ─────────────────────────────────────────┤ ├──TIMESTAMP timestamp-value ───────────────────────────┤ ├──DEFAULT DATABASE ───────────────┬─── NULL ──────┬────┤ │ └─── CURRENT ───┘ │ └──TRANSACTION SHARING ─────────────┬── ON ────────┬────┘ ├── OFF ───────┤ └── DEFAULT ───┘
Expansion of parameter-definition
►►─── parameter-name ── data-type ─┬────────────────┬─────────────────────────►◄ └─ WITH DEFAULT ─┘
Specifies the name of the table procedure being modified. Table-procedure-identifier must identify a table procedure defined in the dictionary.
Identifies the schema associated with the named table procedure. If you do not specify a schema-name, it defaults to:
Defines one or more new parameters to be associated with the table procedure. New parameters are added, in the order specified, after the last existing parameter.
For a description of parameter-definition, see CREATE TABLE PROCEDURE.
Specifies the one- to eight-character name of the program which CA IDMS calls to process references to the table procedure.
Specifies an integer value, in the range of 0 through 2,147,483,647, which represents the average number of rows that the table procedure returns for a given set of input parameters.
Specifies an integer value, in the range of 0 through 2,147,483,647, which represents the average number of disk accesses that the table procedure generates for a given set of input parameters.
Specifies an integer, in the range of 0 through 32767, which represents the size, in bytes, of a local storage area that CA IDMS allocates at runtime and passes to the table procedure on each invocation.
CA IDMS allocates a local storage area on the first call to a table procedure for each SQL statement within a transaction or for a set of SQL statements related through reference to the same cursor. OPEN, CLOSE, FETCH, POSITIONED UPDATE and POSITIONED DELETE statements are related through a cursor. CA IDMS passes the same local storage area to the table procedure for all calls for one statement or related statements. CA IDMS releases the local work area when the SQL statement has completed execution or at the time the cursor is closed.
Specifies an integer, in the range of 0 through 32767, which represents the size, in bytes, of a global storage area that CA IDMS allocates at runtime and passes to the table procedure on each invocation.
CA IDMS allocates a global storage area once within a transaction and retains it until the transaction terminates.
Specifies the one- to four-character identifier for the global storage area. CA IDMS passes the same piece of global storage within a transaction to all routines that have the same global storage key.
If you do not specify a storage key, its value remains unchanged. To remove a storage key, specify NULL as the key.
Specifies the table procedure should execute as a user-mode application program within CA IDMS.
Specifies the table procedure should execute as a system-mode application program. To execute as a system mode application, the program must be fully reentrant and be written in either:
Specifies the value of the synchronization stamp to be assigned to the table procedure. Timestamp-value must be a valid external representation of a timestamp.
Specifies whether a default database should be established for database sessions started by the table procedure.
Specifies that no default database should be established.
Specifies that the database to which the SQL session is connected should become the default for any database session started by the table procedure.
Specifies whether transaction sharing should be enabled for database sessions started by the table procedure. If transaction sharing is enabled for a table procedure's database session, it will share the current SQL session's transaction.
Specifies that transaction sharing should be enabled.
Specifies that transaction sharing should be disabled.
Specifies that the transaction sharing setting that is in effect when the procedure is invoked should be retained.
Parameters for Expansion of parameter-definition
Specifies a 1- to 32-character name of a parameter to be passed to the table procedure. Parameter-name must:
All parameters are implicitly nullable. Input parameters can be assigned NULL as a parameter value and output parameters can return NULL.
Defines the data type for the named parameter. For expanded data-type syntax, see Expansion of Data-type.
Directs CA IDMS to pass a default value for the named parameter if no value for the parameter is specified.
The default value for a parameter is based on its data type:
|
Column data type |
Default value |
|---|---|
|
CHARACTER |
Blanks |
|
VARCHAR |
A character string literal with a length of zero (that is, '') |
|
GRAPHIC |
Double-byte blanks |
|
VARGRAPHIC |
A double-byte character string literal with a length of zero |
|
DATE |
The value in the CURRENT DATE special register |
|
TIME |
The value in the CURRENT TIME special register |
|
TIMESTAMP |
The value in the CURRENT TIMESTAMP special register |
|
All numeric data types |
0 (zero) |
Specifying a Synchronization Stamp
When defining or altering a table procedure, you can specify a value for its synchronization stamp. You should use care when doing so because the purpose of the stamp is to enable the detection of discrepancies between an entity and its definition. If explicitly specified, you must set the synchronization stamp to a new value following a change so that the change is detectable by the runtime system.
If not specified, the synchronization stamp is automatically set to the current date and time.
Adding Parameters to a Table Procedure
The following ALTER TABLE PROCEDURE statement adds two new parameters to the EMP.ORG table procedure:
alter table procedure emp.org
add (job_level decimal(1),
job_title char(20));
|
Copyright © 2014 CA.
All rights reserved.
|
|