Php/docs/function.odbc-foreignkeys
odbc_foreignkeys
(PHP 4, PHP 5, PHP 7)
odbc_foreignkeys — Retrieves a list of foreign keys
说明
odbc_foreignkeys
( resource $connection_id
, string $pk_catalog
, string $pk_schema
, string $pk_table
, string $fk_catalog
, string $fk_schema
, string $fk_table
) : resource|false
Retrieves a list of foreign keys in the specified table or a list of foreign keys in other tables that refer to the primary key in the specified table
参数
connection_id
- ODBC 连接标识符,详见 odbc_connect()。
pk_catalog
- The catalog ('qualifier' in ODBC 2 parlance) of the primary key table.
pk_schema
- The schema ('owner' in ODBC 2 parlance) of the primary key table.
pk_table
- The primary key table.
pk_catalog
- The catalog ('qualifier' in ODBC 2 parlance) of the foreign key table.
fk_schema
- The schema ('owner' in ODBC 2 parlance) of the foreign key table.
fk_table
- The foreign key table.
返回值
Returns an ODBC result identifier 或者在失败时返回 false
.
The result set has the following columns:
PKTABLE_CAT
PKTABLE_SCHEM
PKTABLE_NAME
PKCOLUMN_NAME
FKTABLE_CAT
FKTABLE_SCHEM
FKTABLE_NAME
FKCOLUMN_NAME
KEY_SEQ
UPDATE_RULE
DELETE_RULE
FK_NAME
PK_NAME
DEFERRABILITY
Drivers can report additional columns.
If the foreign keys associated with a primary key are requested, the result set
is ordered by FKTABLE_CAT
, FKTABLE_SCHEM
,
FKTABLE_NAME
and KEY_SEQ
.
If the primary keys associated with a foreign key are requested, the result set
is ordered by PKTABLE_CAT
, PKTABLE_SCHEM
,
PKTABLE_NAME
and KEY_SEQ
.
If pk_table
contains a table name,
odbc_foreignkeys() returns a result set
containing the primary key of the specified table and all of the
foreign keys that refer to it.
If fk_table
contains a table name,
odbc_foreignkeys() returns a result set
containing all of the foreign keys in the specified table and the
primary keys (in other tables) to which they refer.
If both pk_table
and
fk_table
contain table names,
odbc_foreignkeys() returns the foreign keys in
the table specified in fk_table
that refer
to the primary key of the table specified in
pk_table
. This should be one key at most.
参见
- odbc_tables() - Get the list of table names stored in a specific data source
- odbc_primarykeys() - Gets the primary keys for a table