mi_integer mi_column_id(row_desc, colname)
   MI_ROW_DESC *row_desc;
   mi_string *colname;

row_desc

is a pointer to the row descriptor for the row that contains the specified column.

colname

is a pointer to a null-terminated string to contain the column name.

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

A row descriptor can describe the structure of a row in a table or the structure of a row type. From the row descriptor that row_desc references, the mi_column_id( ) function obtains a column identifier for either structure:

• The column identifier of the colname column in the row
• The column identifier of the colname field for the row type

A column identifier is the position of the column or field within the row descriptor. Column numbering follows C array-indexing conventions: the first column in the row is at position zero (0).

>=0

is the column position of the specified column or field in the specified row descriptor.

MI_ERROR

indicates that the function was not successful.

See also the descriptions of mi_column_count( ), mi_column_name( ), mi_column_nullable( ), mi_column_precision( ), mi_column_scale( ), mi_column_type_id( ), mi_column_typedesc( ), mi_get_row_desc( ), and mi_get_row_desc_without_row( ).

For more information about row descriptors, see the IBM Informix: DataBlade API Programmer's Guide.