# db2_primary_keys

(PECL ibm_db2 >= 1.0.0)

db2_primary_keys — Returns a result set listing primary keys for a table

### 说明

db2_primary_keys ( resource `$connection` , string `$qualifier` , string `$schema` , string `$table-name` ) : resource

Returns a result set listing the primary keys for a table.

### 参数

`connection`

  A valid connection to an IBM DB2, Cloudscape, or Apache Derby database.

`qualifier`

  A qualifier for DB2 databases running on OS/390 or z/OS servers. For other databases, pass `NULL` or an empty string.

`schema`

  The schema which contains the tables. If `schema` is `NULL`, db2_primary_keys() matches the schema for the current connection.

`table-name`

  The name of the table.

### 返回值

Returns a statement resource with a result set containing rows describing the primary keys for the specified table. The result set is composed of the following columns:

Column name | Description
--- | ---
TABLE_CAT | Name of the catalog for the table containing the primary key. The value is NULL if this table does not have catalogs.
TABLE_SCHEM | Name of the schema for the table containing the primary key.
TABLE_NAME | Name of the table containing the primary key.
COLUMN_NAME | Name of the column containing the primary key.
KEY_SEQ | 1-indexed position of the column in the key.
PK_NAME | The name of the primary key.

### 参见

- db2_column_privileges() - Returns a result set listing the columns and associated privileges for a table
- db2_columns() - Returns a result set listing the columns and associated metadata for a table
- db2_foreign_keys() - Returns a result set listing the foreign keys for a table
- db2_procedure_columns() - Returns a result set listing stored procedure parameters
- db2_procedures() - Returns a result set listing the stored procedures registered in a database
- db2_special_columns() - Returns a result set listing the unique row identifier columns for a table
- db2_statistics() - Returns a result set listing the index and statistics for a table
- db2_table_privileges() - Returns a result set listing the tables and associated privileges in a database
- db2_tables() - Returns a result set listing the tables and associated metadata in a database