SQLStatistics returns information about a single table as a standard result set, ordered by NON_UNIQUE, TYPE, INDEX_QUALIFIER, INDEX_NAME, and ORDINAL_POSITION. The result set combines statistics information (in the CARDINALITY and PAGES columns of the result set) for the table with information about each index. For information about how this information might be used, see Uses of Catalog Data.
To determine the actual lengths of the TABLE_CAT, TABLE_SCHEM, TABLE_NAME, and COLUMN_NAME columns, an application can call SQLGetInfo with the SQL_MAX_CATALOG_NAME_LEN, SQL_MAX_SCHEMA_NAME_LEN, SQL_MAX_TABLE_NAME_LEN, and SQL_MAX_COLUMN_NAME_LEN options.
.gif) Note |
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| For more information about the general use, arguments, and returned data of ODBC catalog functions, see Catalog Functions. |
The following columns have been renamed for ODBC 3.x. The column name changes do not affect backward compatibility because applications bind by column number.
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ODBC 2.0 column
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ODBC 3.x column
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| TABLE_QUALIFIER | TABLE_CAT |
| TABLE_OWNER | TABLE_SCHEM |
| SEQ_IN_INDEX | ORDINAL_POSITION |
| COLLATION | ASC_OR_DESC |
The following table lists the columns in the result set. Additional columns beyond column 13 (FILTER_CONDITION) can be defined by the driver. An application should gain access to driver-specific columns by counting down from the end of the result set instead of specifying an explicit ordinal position. For more information, see Data Returned by Catalog Functions.
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Column name
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Column number
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Data type
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Comments
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| TABLE_CAT (ODBC 1.0) | 1 | Varchar | Catalog name of the table to which the statistic or index applies; NULL if not applicable to the data source. If a driver supports catalogs for some tables but not for others, such as when the driver retrieves data from different DBMSs, it returns an empty string ("") for those tables that do not have catalogs. |
| TABLE_SCHEM (ODBC 1.0) | 2 | Varchar | Schema name of the table to which the statistic or index applies; NULL if not applicable to the data source. If a driver supports schemas for some tables but not for others, such as when the driver retrieves data from different DBMSs, it returns an empty string ("") for those tables that do not have schemas. |
| TABLE_NAME (ODBC 1.0) | 3 | Varchar not NULL | Table name of the table to which the statistic or index applies. |
| NON_UNIQUE (ODBC 1.0) | 4 | Smallint | Indicates whether the index does not allow duplicate values: SQL_TRUE if the index values can be nonunique. SQL_FALSE if the index values must be unique. NULL is returned if TYPE is SQL_TABLE_STAT. |
| INDEX_QUALIFIER (ODBC 1.0) | 5 | Varchar | The identifier that is used to qualify the index name doing a DROP INDEX; NULL is returned if an index qualifier is not supported by the data source or if TYPE is SQL_TABLE_STAT. If a non-null value is returned in this column, it must be used to qualify the index name on a DROP INDEX statement; otherwise, the TABLE_SCHEM should be used to qualify the index name. |
| INDEX_NAME (ODBC 1.0) | 6 | Varchar | Index name; NULL is returned if TYPE is SQL_TABLE_STAT. |
| TYPE (ODBC 1.0) | 7 | Smallint not NULL | Type of information being returned: SQL_TABLE_STAT indicates a statistic for the table (in the CARDINALITY or PAGES column). SQL_INDEX_BTREE indicates a B-Tree index. SQL_INDEX_CLUSTERED indicates a clustered index. SQL_INDEX_CONTENT indicates a content index. SQL_INDEX_HASHED indicates a hashed index. SQL_INDEX_OTHER indicates another type of index. |
| ORDINAL_POSITION (ODBC 1.0) | 8 | Smallint | Column sequence number in index (starting with 1); NULL is returned if TYPE is SQL_TABLE_STAT. |
| COLUMN_NAME (ODBC 1.0) | 9 | Varchar | Column name. If the column is based on an expression, such as SALARY + BENEFITS, the expression is returned; if the expression cannot be determined, an empty string is returned. NULL is returned if TYPE is SQL_TABLE_STAT. |
| ASC_OR_DESC (ODBC 1.0) | 10 | Char(1) | Sort sequence for the column: "A" for ascending; "D" for descending; NULL is returned if column sort sequence is not supported by the data source or if TYPE is SQL_TABLE_STAT. |
| CARDINALITY (ODBC 1.0) | 11 | Integer | Cardinality of table or index; number of rows in table if TYPE is SQL_TABLE_STAT; number of unique values in the index if TYPE is not SQL_TABLE_STAT; NULL is returned if the value is not available from the data source. |
| PAGES (ODBC 1.0) | 12 | Integer | Number of pages used to store the index or table; number of pages for the table if TYPE is SQL_TABLE_STAT; number of pages for the index if TYPE is not SQL_TABLE_STAT; NULL is returned if the value is not available from the data source or if not applicable to the data source. |
| FILTER_CONDITION (ODBC 2.0) | 13 | Varchar | If the index is a filtered index, this is the filter condition, such as SALARY > 30000; if the filter condition cannot be determined, this is an empty string. NULL if the index is not a filtered index, it cannot be determined whether the index is a filtered index, or TYPE is SQL_TABLE_STAT. |
If the row in the result set corresponds to a table, the driver sets TYPE to SQL_TABLE_STAT and sets NON_UNIQUE, INDEX_QUALIFIER, INDEX_NAME, ORDINAL_POSITION, COLUMN_NAME, and ASC_OR_DESC to NULL. If CARDINALITY or PAGES are not available from the data source, the driver sets them to NULL.