SQLGetTypeInfo function (CLI) - Get data type information

SQLRETURN   SQLGetTypeInfo (
               SQLHSTMT          StatementHandle,  /* hstmt */
               SQLSMALLINT       DataType);        /* fSqlType */

Column 1  TYPE_NAME (VARCHAR(128) NOT NULL Data Type)

Data source-dependent data type name; for example, "CHAR()", "LONG VARBINARY". Applications must use this name in the CREATE TABLE and ALTER TABLE statements.

Column 2  DATA_TYPE (SMALLINT NOT NULL Data Type)

SQL data type define values, for example, SQL_VARCHAR, SQL_BLOB, SQL_DATE, SQL_INTEGER.

Column 3  COLUMN_SIZE (INTEGER Data Type)

If the data type is a character or binary string, then this column contains the maximum length in bytes; if it is a graphic (DBCS) string, this is the number of double byte characters for the column (the CLI/ODBC configuration keyword Graphic can change this default behaviour). If the data type is XML, zero is returned.

For date, time, timestamp data types, this is the total number of characters required to display the value when converted to character.

For numeric data types, this is the total number of digits (precision).

Column 4  LITERAL_PREFIX (VARCHAR(128) Data Type)

Character that DB2® recognizes as a prefix for a literal of this data type. This column is null for data types where a literal prefix is not applicable.

Column 5  LITERAL_SUFFIX (VARCHAR(128) Data Type)

Character that DB2 recognizes as a suffix for a literal of this data type. This column is null for data types where a literal prefix is not applicable.

Column 6  CREATE_PARAMS (VARCHAR(128) Data Type)

The text of this column contains a list of keywords, separated by commas, corresponding to each parameter the application might specify in parenthesis when using the name in the TYPE_NAME column as a data type in SQL. The keywords in the list can be LENGTH, PRECISION, or SCALE. They appear in the order that the SQL syntax requires that they be used.

A NULL indicator is returned if there are no parameters for the data type definition, (such as INTEGER).

Note: The intent of CREATE_PARAMS is to enable an application to customize the interface for a DDL builder. An application should expect, using this, only to be able to determine the number of arguments required to define the data type and to have localized text that could be used to label an edit control.

Column 7  NULLABLE (SMALLINT NOT NULL Data Type)

Indicates whether the data type accepts a NULL value

• Set to SQL_NO_NULLS if NULL values are disallowed.
• Set to SQL_NULLABLE if NULL values are allowed.
• Set to SQL_NULLABLE_UNKNOWN if it is not known whether NULL values are allowed or not.

Column 8  CASE_SENSITIVE (SMALLINT NOT NULL Data Type)

Indicates whether a character data type is case-sensitive in collations and comparisons. Valid values are SQL_TRUE and SQL_FALSE.

Column 9  SEARCHABLE (SMALLINT NOT NULL Data Type)

Indicates how the data type is used in a WHERE clause. Valid values are:

• SQL_UNSEARCHABLE : if the data type cannot be used in a WHERE clause.
• SQL_LIKE_ONLY : if the data type can be used in a WHERE clause only with the LIKE predicate.
• SQL_ALL_EXCEPT_LIKE : if the data type can be used in a WHERE clause with all comparison operators except LIKE.
• SQL_SEARCHABLE : if the data type can be used in a WHERE clause with any comparison operator.

Column 10  UNSIGNED_ATTRIBUTE (SMALLINT Data Type)

Indicates whether the data type is unsigned. The valid values are: SQL_TRUE, SQL_FALSE or NULL. A NULL indicator is returned if this attribute is not applicable to the data type.

Column 11  FIXED_PREC_SCALE (SMALLINT NOT NULL Data Type)

Contains the value SQL_TRUE if the data type is exact numeric and always has the same precision and scale; otherwise, it contains SQL_FALSE.

Column 12  AUTO_INCREMENT (SMALLINT Data Type)

Contains SQL_TRUE if a column of this data type is automatically set to a unique value when a row is inserted; otherwise, contains SQL_FALSE.

Column 13  LOCAL_TYPE_NAME (VARCHAR(128) Data Type)

This column contains any localized (native language) name for the data type that is different from the regular name of the data type. If there is no localized name, this column is NULL.

This column is intended for display only. The character set of the string is locale-dependent and is typically the default character set of the database.

Column 14  MINIMUM_SCALE (INTEGER Data Type)

The minimum scale of the SQL data type. If a data type has a fixed scale, the MINIMUM_SCALE and MAXIMUM_SCALE columns both contain the same value. NULL is returned where scale is not applicable.

Column 15  MAXIMUM_SCALE (INTEGER Data Type)

The maximum scale of the SQL data type. NULL is returned where scale is not applicable. If the maximum scale is not defined separately in the DBMS, but is defined instead to be the same as the maximum length of the column, then this column contains the same value as the COLUMN_SIZE column.

Column 16  SQL_DATA_TYPE (SMALLINT NOT NULL Data Type)

The value of the SQL data type as it appears in the SQL_DESC_TYPE field of the descriptor. This column is the same as the DATA_TYPE column (except for interval and datetime data types which CLI does not support).

Column 17  SQL_DATETIME_SUB (SMALLINT Data Type)

This field is always NULL (CLI does not support interval and datetime data types).

Column 18  NUM_PREC_RADIX (INTEGER Data Type)

If the data type is an approximate numeric type, this column contains the value 2 to indicate that COLUMN_SIZE specifies a number of bits. For exact numeric types, this column contains the value 10 to indicate that COLUMN_SIZE specifies a number of decimal digits. Otherwise, this column is NULL.

Column 19  INTERVAL_PRECISION (SMALLINT Data Type)

This field is always NULL (CLI does not support interval data types).