A SQL descriptor is an area of memory that stores a description of the variables used in a prepared dynamic SQL statement. A SQL descriptor can contain the following information about data attributes (for details, see the descriptions of the set descriptor and get descriptor commands in Chapter 10, “Embedded SQL Statements: Reference Pages”):
precision – integer.
scale – integer.
nullable – 1 (cs_true) if the column can contain nulls; 0 (cs_false) if it cannot. Valid only with get descriptor statement.
indicator – value for the indicator associated with the dynamic parameter marker. Valid only with get descriptor statement.
name – name of the dynamic parameter marker. Valid only with get descriptor statement.
data – value for the dynamic parameter marker specified by the item number. If the value of indicator is -1, the value of data is undefined.
count – number of dynamic parameter markers described in the descriptor.
type – datatype of the dynamic parameter marker or host variable.
returned_length – actual length of the data in an output column.