OPEN FOR Statement

13.46 OPEN FOR Statement

The OPEN FOR statement associates a cursor variable with a query, allocates database resources to process the query, identifies the result set, and positions the cursor before the first row of the result set.

If the query has a FOR UPDATE clause, then the OPEN FOR statement locks the rows of the result set.

Topics

Syntax

open_for_statement ::=

Description of the illustration open_for_statement.eps

using_clause ::=

Description of the illustration using_clause.eps

Semantics

open_for_statement

cursor_variable

Name of a cursor variable. If cursor_variable is the formal parameter of a subprogram, then it must not have a return type. For information about cursor variables as subprogram parameters, see "Cursor Variables as Subprogram Parameters".

:host_cursor_variable

Name of a cursor variable that was declared in a PL/SQL host environment and passed to PL/SQL as a bind variable. Do not put space between the colon (:) and host_cursor_variable.

The data type of a host cursor variable is compatible with the return type of any PL/SQL cursor variable.

select_statement

SQL SELECT statement (not a PL/SQL SELECT INTO statement). Typically, select_statement returns multiple rows.

See:

Oracle Database SQL Language Reference for SELECT statement syntax

dynamic_string

String literal, string variable, or string expression of the data type CHAR, VARCHAR2, or CLOB, which represents a SQL SELECT statement. Typically, dynamic_statement represents a SQL SELECT statement that returns multiple rows.

using_clause

Specifies bind variables, using positional notation.

Note:

If you repeat placeholder names in dynamic_sql_statement, be aware that the way placeholders are associated with bind variables depends on the kind of dynamic SQL statement. For details, see "Repeated Placeholder Names in Dynamic SQL Statements."

Restriction on using_clause

Use if and only if select_statement or dynamic_sql_stmt includes placeholders for bind variables.

IN, OUT, IN OUT

Parameter modes of bind variables. An IN bind variable passes its value to the select_statement or dynamic_string. An OUT bind variable stores a value that dynamic_string returns. An IN OUT bind variable passes its initial value to dynamic_string and stores a value that dynamic_string returns. Default: IN.

bind_argument

Expression whose value replaces its corresponding placeholder in select_statement or dynamic_string at run time. You must specify a bind_argument for every placeholder.

Note:

Bind variables can be evaluated in any order. If a program determines order of evaluation, then at the point where the program does so, its behavior is undefined.

Restrictions on bind_argument

bind_argument cannot be an associative array indexed by string.
bind_argument cannot be the reserved word NULL.

To pass the value NULL to the dynamic SQL statement, use an uninitialized variable where you want to use NULL, as in Example 7-7.

Examples

Example 6-26, "Fetching Data with Cursor Variables"
Example 6-30, "Querying a Collection with Static SQL"
Example 6-31, "Procedure to Open Cursor Variable for One Query"
Example 6-32, "Opening Cursor Variable for Chosen Query (Same Return Type)"
Example 6-33, "Opening Cursor Variable for Chosen Query (Different Return Types)"
Example 7-8, "Native Dynamic SQL with OPEN FOR, FETCH, and CLOSE Statements"
Example 7-9, "Querying a Collection with Native Dynamic SQL"