READ RESULT SET (SQL)

Common Set Syntax:

`READ` [(`limit`)] `RESULT SET` `result-set` `INTO`		`VIEW` `view-name` `parameter` [, `parameter`]...	`FROM` `ddm-name`
[`GIVING` [:] `sql-code`]
`END-RESULT`	(structured mode only)
`LOOP`	(reporting mode only)

Extended Set Syntax:

`READ` [(`limit`)] `RESULT SET` `result-set` `INTO`		`VIEW` `view-name` `parameter` [, `parameter`]...	`FROM` `ddm-name`
[`WITH INSENSITIVE SCROLL` [:] `scroll-hv`]
[`GIVING` [:] `sql-code`]
[`WITH ROWSET POSITIONING FOR`		[:] `row_hv` `integer`	`ROWS`]
`END-RESULT`	(structured mode only)
`LOOP`	(reporting mode only)

This document covers the following topics:

Function
Restriction
Syntax Description
Example

For an explanation of the symbols used in the syntax diagram, see Syntax Symbols.

Belongs to Function Group: Database Access and Update

See also READ RESULT SET - SQL in the Natural for DB2 part of the Database Management System Interfaces documentation.

Function

The SQL statement READ RESULT SET can only be used in conjunction with a CALLDBPROC statement. It is used to read a result set which was created by a stored procedure that was invoked by a previous CALLDBPROC statement.

Restriction

This statement is available only with Natural for DB2.

Syntax Description

Syntax Element	Description
`limit`	Limit Option: You can limit the number of rows to be read. You can specify the limit either as a numeric constant (`0 - 4294967295`) or as a variable of format N, P or I.
`result-set`	Result Set: As `result-set` you specify a result-set locator variable filled by a preceding `CALLDBPROC` statement. `result-set` has to be a variable of format/length I4. Note: If a syncpoint operation takes place between the `CALLDBPROC` statement and the `READ RESULT SET` statement, the result sets can no longer be accessed by the `READ RESULT SET` statement.
`INTO`	INTO Clause: The `INTO` clause is used to specify the target fields in the program which are to be filled with the result set. The `INTO` clause can specify either single parameters or one or more views as defined in the `DEFINE DATA` statement.
`VIEW` `view-name`	VIEW Clause: `view-name` specifies a view whose fields receive the columns of the result set created by the stored procedure invoked via the `CALLDBPROC` statement. The number of columns of the result set must correspond to the number of fields defined in the view (not counting group fields, redefining fields and indicator fields).
`parameter`	Parameter: Each `parameter` specifies a field which receives a column of the result set created by the stored procedure invoked via the `CALLDBPROC` statement.
`FROM ddm-name`	DDM Name: As `ddm-name` you specify the name of the data definition module (DDM) which is used to "address" the database executing the stored procedure. For further information, see `ddm-name`.
`WITH INSENSITIVE SCROLL` `[:] scroll_hv`	WITH INSENSITIVE SCROLL Clause: This clause belongs to the SQL Extended Set. It is available only with Natural for DB2. Using this clause causes the application to use an insensitive scrollable cursor to access the result set created by the previously invoked stored procedure. In order to use this clause, the stored procedure must have created the result set with a scrollable cursor. `scroll_hv` has to be an alphanumeric Natural variable which contains the scrolling direction. `scroll_hv` will be evaluated each time the `READ RESULT SET` processing loop is executed. If the `GIVING sqlcode` option is specified as well, the processing loop will stay open, even if an `sqlcode +100` (row not found) is returned from the RDBMS. The processing will be terminated, if the application issues an `ESCAPE` statement or if the SQLCODE `+100` (row not found) is encountered five times successively without a terminal I/O. If the `GIVING sqlcode` option is not specified, the processing loop will be closed, if any SQLCODE other than 0 (success) is returned from the RDBMS.
`GIVING sqlcode`	GIVING `sqlcode` Clause: This clause may be used to obtain the SQLCODE of the SQL "fetch" operation used to process the result set. If this clause is specified and the SQLCODE of the SQL operation is not `0`, no Natural error message will be issued. In this case, the action to be taken in reaction to the SQLCODE value has to be coded in the invoking Natural object. The `sqlcode` field has to be a variable of format/length I4. If the `GIVING sqlcode` clause is omitted, a Natural error message will be issued if the SQLCODE is not `0`.
`WITH ROWSET POSITIONING FOR ... ROWS`	WITH ROWSET POSITIONING FOR ... ROWS Clause: This clause belongs to the SQL Extended Set. It is available only with Natural for DB2. Using this clause causes the application to read multiple rows of data from the result set by the previously invoked stored procedure. The `integer` or `:row_hv` variable determines the number of rows fetched. If the `GIVING sqlcode` option is specified as well, the processing loop will stay open, even if an SQLCODE `+100` (row not found) is returned from the RDBMS. The processing will be terminated, if the application issues an `ESCAPE` statement or if the SQLCODE `+100` (row not found) is encountered five times successively without a terminal I/O. If the `GIVING sqlcode` clause is not specified, the processing loop will be closed if any SQLCODE other than `0` (success) is returned from the RDBMS.
`END-RESULT`	End of READ RESULT SET Statement: In structured mode, the Natural reserved keyword `END-RESULT` must be used to end the `READ RESULT SET` statement. In reporting mode, the Natural statement `LOOP` must be used to end the `READ RESULT SET` statement.
`LOOP`

Example

See Example of CALLDBPROC/READ RESULT SET in the section CALLDBPROC - SQL of the Natural for DB2 documentation.