SET variable

The SET variable statement produces a result table consisting of at most one row and assigns the values in that row to variables.

Invocation

This statement can only be embedded in an application program. It is an executable statement that cannot be dynamically prepared. It must not be specified in REXX.

Authorization

If a row-fullselect is specified, see fullselect for an explanation of the authorization required for each subselect.

Syntax

Click to skip syntax diagram

Read syntax diagramSkip visual syntax diagram        .-,---------------------------------------------------------.
        V                                                           |
>>-SET----+-variable-- = --+-expression-+-------------------------+-+-><
          |                '-NULL-------'                         |
          |    .-,--------.               .-,--------------.      |
          |    V          |               V                |      |
          '-(----variable-+--)-- = --(--+---+-expression-+-+-+--)-'
                                        |   '-NULL-------'   |
                                        '-row-fullselect-----'
 

Description

variable, ...
Identifies one or more variables or host structures that must be declared in accordance with the rules for declaring variables (see References to host variables). A host structure is logically replaced by a list of variables that represent each of the elements of the host structure.

The value to be assigned to each variable can be specified immediately following the variable, for example, variable = expression, variable = expression. Or, sets of parentheses can be used to specify all the variables and then all the values, for example, (variable, variable) = (expression, expression).

The data type of each variable must be compatible with its corresponding result column. Each assignment is made according to the rules described in Assignments and comparisons. The number of variables specified to the left of the equal operator must equal the number of values in the corresponding result specified to the right of the equal operator. If the value is null, an indicator variable must be provided. If an assignment error occurs, the value is not assigned to the variable, and no more values are assigned to variables. Any values that have already been assigned to variables remain assigned.

If an error occurs as the result of an arithmetic expression in the expression or SELECT list of the subselect (division by zero, or overflow) or a character conversion error occurs, the result is the null value. As in any other case of a null value, an indicator variable must be provided. The value of the variable is undefined. In this case, however, the indicator variable is set to -2. Processing of the statement continues as if the error had not occurred. (However, a warning is returned.) If you do not provide an indicator variable, an error is returned. It is possible that some values have already been assigned to variables and will remain assigned when the error occurs.

expression
Specifies the new value of the variable. The expression is any expression of the type described in Expressions. It must not include a column name.
NULL
Specifies that the new value for the variable is the null value.
row-fullselect
A fullselect that returns a single result row. The result column values are assigned to each corresponding variable. If the result of the fullselect is no rows, then null values are assigned. An error is returned if there is more than one row in the result.

Notes

Variable assignment: If the specified variable is character and is not large enough to contain the result, a warning (SQLSTATE 01004) is returned (and 'W' is assigned to SQLWARN1 in the SQLCA). The actual length of the result is returned in the indicator variable associated with the variable, if an indicator variable is provided.

If the specified variable is a C NUL-terminated variable and is not large enough to contain the result and the NUL-terminator:

Examples

Example 1: Assign the value of the CURRENT PATH special register to host variable HV1.

   EXEC SQL SET :HV1 = CURRENT PATH;

Example 2: Assume that LOB locator LOB1 is associated with a CLOB value. Assign a portion of the CLOB value to host variable DETAILS using the LOB locator.

   EXEC SQL SET :DETAILS = SUBSTR(:LOB1,1,35);


[ Top of Page | Previous Page | Next Page | Contents | Index ]