Indicator Variables

 

Indicator Variables

1.       Function: Processing NULL Data

2.       The value of Indicator Variable (SMALLINT)

l         >=0 (usually 0), indicate that the column is not NULL

l         <0 (usually -1), indicate that the column is NULL

l         -2, indicate that the column value can’t be stored in host variable for the reason that numeric conversion could not be performed or arithmetic expression error occurred

l         -3, indicate that a hole was detected for the row on a multiple row FETCH, and values were not returned for the row. SQLCODE +222, is also returned for that row.

3.       Indicator Variable Usage

l         When using SELECT or FETCH statement in SQL, indicator variables are set by DB2 according to the property of the relevant column(NULL or NOT NULL)

l         When using UPDATE or INSERT statement in SQL, the programmer need to set the value of indicator variables to tell DB2 that the relevant column is NULL or NOT NULL