|
Describes the name and type information for the columns of a cursor.
sa_describe_cursor( cursor_name )
This VARCHAR(256) value identifies the open cursor to describe.
| Column name | Data type | Description |
|---|---|---|
| column_number | INTEGER | The ordinal position of the column described by this row, starting at 1. |
| name | VARCHAR(128) | The name of the column. |
| domain_id | SMALLINT | The data type of the column. |
| domain_name | VARCHAR(128) | The data type name of the column. |
| domain_name_with_size | VARCHAR(160) | The data type name, including size and precision (as used in CREATE TABLE or CAST functions). |
| width | INTEGER | The length of a string parameter, the precision of a numeric parameter, or the number of bytes of storage for any other data type. |
| scale | INTEGER | The number of digits after the decimal point for numeric data type columns, and zero for all other data types. |
| declared_width | INTEGER | The length of a string parameter, the precision of a numeric parameter, or the number of bytes of storage for any other data type. |
| user_type_id | SMALLINT | The user-defined data type if applicable, otherwise NULL. |
| user_type_name | VARCHAR(128) | The user-defined data type if applicable, otherwise NULL. |
| correlation_name | VARCHAR(128) | The correlation name associated with the expression if applicable, otherwise NULL. |
| base_table_id | UNSIGNED INTEGER | The table_id if the expression is a column, otherwise NULL. |
| base_column_id | UNSIGNED INTEGER | The column_id if the expression is a column, otherwise NULL. |
| base_owner_name | VARCHAR(128) | The owner name if the expression is a column, otherwise NULL. |
| base_table_name | VARCHAR(128) | The table name if the expression is a column, otherwise NULL. |
| base_column_name | VARCHAR(128) | The column name if the expression is a column, otherwise NULL. |
| nulls_allowed | BIT | The indicator whether the expression can be NULL (1). |
| is_autoincrement | BIT | An indicator whether the expression is an AUTOINCREMENT column (1). |
| is_key_column | BIT | An indicator whether the expression is part of a key for the result set (1). For more information, see the Remarks section below. |
| is_added_key_column | BIT | An indicator whether the expression is an added key column (1). For more information, see the Remarks section below. |
The sa_describe_cursor system procedure provides an API-independent mechanism for retrieving the description of the columns returned by the cursor. The system procedure can be useful when writing stored procedures that work with dynamic SQL.
The sa_describe_cursor system procedure can be used in a CALL statement or in the FROM clause of a SELECT statement.
cursor_name must refer to an open cursor in the current connection. Use the sa_list_cursors system procedure to get the list of open cursors for the connection.
You must have EXECUTE privilege on the system procedure.
None
The following batch creates a cursor named myCursor on the Products table and then opens it. The sa_describe_cursor system procedure is used to describe the columns of the cursor. A result set containing 5 rows, one for each column, is produced.
BEGIN
DECLARE myCursor CURSOR FOR
SELECT ID, Name, Description, Color, Quantity FROM Products;
OPEN myCursor;
CALL sa_describe_cursor( 'myCursor' );
CLOSE myCursor;
END