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PROCEDURE_COLUMNS Rowset

GUID: DBSCHEMA_PROCEDURE_COLUMNS

Number of restriction columns: 4

Restriction columns: PROCEDURE_CATALOG, PROCEDURE_SCHEMA, PROCEDURE_NAME, COLUMN_NAME

Default sort order: PROCEDURE_CATALOG, PROCEDURE_SCHEMA, PROCEDURE_NAME

Description: The PROCEDURE_COLUMNS rowset returns information about the columns of rowsets returned by procedures.

Column name

Type indicator

Description

PROCEDURE_CATALOG

DBTYPE_WSTR

Catalog name. NULL if the provider does not support catalogs.

PROCEDURE_SCHEMA

DBTYPE_WSTR

Unqualified schema name. NULL if the provider does not support schemas.

PROCEDURE_NAME

DBTYPE_WSTR

Table name.

COLUMN_NAME

DBTYPE_WSTR

The name of the column; this might not be unique. If this cannot be determined, a NULL is returned.

This column, together with the COLUMN_GUID and COLUMN_PROPID columns, forms the column ID. One or more of these columns will be NULL, depending on which elements of the DBID structure the provider uses.

COLUMN_GUID

DBTYPE_GUID

Column GUID.

COLUMN_PROPID

DBTYPE_UI4

Column property ID.

ROWSET_NUMBER

DBTYPE_UI4

Number of the rowset containing the column. This is greater than one only if the procedure returns multiple rowsets.

ORDINAL_POSITION

DBTYPE_UI4

The ordinal of the column. Columns are numbered starting from one. NULL if there is no stable ordinal value for the column.

IS_NULLABLE

DBTYPE_BOOL

VARIANT_TRUE ? The column might be nullable.

VARIANT_FALSE ? The column is known not to be nullable.

DATA_TYPE

DBTYPE_UI2

The indicator of the column's data type. If the data type of the column varies from row to row, this must be DBTYPE_VARIANT. For a list of valid type indicators, see Type Indicators in Appendix A.

TYPE_GUID

DBTYPE_GUID

The GUID of the column's data type.

CHARACTER_MAXIMUM_LENGTH

DBTYPE_UI4

The maximum possible length of a value in the column. For character, binary, or bit columns, this is one of the following:

  • The maximum length of the column in characters, bytes, or bits, respectively, if one is defined. For example, a CHAR(5) column in an SQL table has a maximum length of five (5).

  • The maximum length of the data type in characters, bytes, or bits, respectively, if the column does not have a defined length.

  • Zero (0) if neither the column nor the data type has a defined maximum length.

NULL for all other types of columns.

CHARACTER_OCTET_LENGTH

DBTYPE_UI4

Maximum length in octets (bytes) of the column, if the type of the column is character or binary. A value of zero means the column has no maximum length. NULL for all other types of columns.

NUMERIC_PRECISION

DBTYPE_UI2

If the column's data type is of a numeric data type other than VARNUMERIC, this is the maximum precision of the column. The precision of columns with a data type of DBTYPE_DECIMAL or DBTYPE_NUMERIC depends on the definition of the column. For the precision of all other numeric data types, see Precision of Numeric Data Types in Appendix A.

If the column's data type is not numeric or is VARNUMERIC, this is NULL.

NUMERIC_SCALE

DBTYPE_I2

If the column's type indicator is DBTYPE_DECIMAL, DBTYPE_NUMERIC, or DBTYPE_VARNUMERIC, this is the number of digits to the right of the decimal point. Otherwise, this is NULL.

DESCRIPTION

DBTYPE_WSTR

Human-readable description of the column. For example, the description for a column named Name in the Employee table might be "Employee name."