Informix DataBlade API Programmer's Manual DataBlade API Function Descriptions

The mi_parameter_scale() function returns the scale of the column that is associated with a specified input parameter in a prepared statement.

mi_integer mi_parameter_scale(stmt_desc, param_id)

MI_STATEMENT *stmt_desc;

mi_integer param_id;

stmt_desc	is a pointer to the statement descriptor for the prepared statement that contains the input parameter.
param_id	indicates the parameter identifier of the column, which specifies the position of the input parameter in the specified statement descriptor. Input-parameter numbering follows C programming conventions: the first parameter in the statement is at position zero (0).

Valid in Client LIBMI Application?	Valid in User-Defined Routine?
Yes	Yes

The mi_parameter_scale() function obtains the column scale of the column that is associated with param_id from the statement descriptor that stmt_desc references. This function is an accessor function for a statement descriptor, which describes a prepared statement. The statement descriptor stores information about the scales of input-parameter columns in the zero-based parameter-scale array. To obtain information about the nth input parameter, use a param_id value of n-1.

The scale is an attribute of the data type. The meaning of the scale depends on the associated data type, as the following table shows.

If you call mi_parameter_scale() on some other data type, the function returns zero (0).

Parameter information is available only for the INSERT and UPDATE statements. Support for the UPDATE statement includes the following forms of UPDATE:

• UPDATE with or without a WHERE clause
• UPDATE WHERE CURRENT OF

If you attempt to request parameter information for other SQL statements, mi_parameter_scale() raises an exception.

See the descriptions of the following functions: mi_close_statement(), mi_exec_prepared_statement(), mi_fetch_statement(), mi_get_statement_row_desc(), mi_parameter_count(), mi_parameter_nullable(), mi_parameter_precision(), mi_parameter_type_id(), mi_parameter_type_name(), mi_prepare(), and mi_statement_command_name().