FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE referential_action ] [ ON UPDATE referential_action ] } [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ] an...
CHECK ( expression ) | FOREIGN KEY ( column_name [, ... ] ) REFERENCES ref_table [ ( ref_column [, ... ] ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE action ] [ ON UPDATE action ] } [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE...
ccu.column_name AS foreign_column_name, tc.is_deferrable,tc.initially_deferred FROM information_schema.table_constraints AS tc JOIN information_schema.key_column_usage AS kcu ON tc.constraint_name = kcu.constraint_name JOIN information_schema.constraint_column_usage AS ccu ON ccu.constraint_name ...
CHECK ( expression ) | FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE action ] [ ON UPDATE action ] } [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]...
Command:CREATETRIGGERDescription:define anewtriggerSyntax:CREATE[CONSTRAINT]TRIGGERname{BEFORE|AFTER|INSTEADOF}{event[OR...]}ONtable_name[FROMreferenced_table_name]{NOTDEFERRABLE|[DEFERRABLE]{INITIALLYIMMEDIATE|INITIALLYDEFERRED}}[FOR[EACH]{ROW|STATEMENT}][WHEN(condition)]EXECUTEPROCEDUREfunction_name(argume...
DETAIL: Key (emp_id)=(1)isnotpresentintable"emp". 3、允许延判,在事务开启后设置事务结束延判 postgres=#altertablelocalterconstraintloc_emp_id_fkey deferrable;ALTERTABLEpostgres=#begin;BEGINpostgres=#insertintolocvalues(1,1); ERROR:insertorupdateontable"loc" violatesforeignkeyconstraint"loc_emp_id...
The difference only arises when you define the foreign key constraint as DEFERRABLE with an INITIALLY DEFERRED or INITIALLY IMMEDIATE mode. We’ll discuss more on this in the upcoming tutorial. SET NULL The SET NULL automatically sets NULL to the foreign key columns in the referencing rows of ...
FOREIGN KEY ( column_name [, ... ] ) REFERENCES reftable [ ( refcolumn [, ... ] ) ] [ MATCH FULL | MATCH PARTIAL | MATCH SIMPLE ] [ ON DELETE action ] [ ON UPDATE action ] } [ DEFERRABLE | NOT DEFERRABLE ] [ INITIALLY DEFERRED | INITIALLY IMMEDIATE ]...
ccu.column_name AS foreign_column_name, tc.is_deferrable,tc.initially_deferred FROM information_schema.table_constraints AS tc JOIN information_schema.key_column_usage AS kcu ON tc.constraint_name = kcu.constraint_name JOIN information_schema.constraint_column_usage AS ccu ON ccu.constraint_name...
tc.is_deferrable,tc.initially_deferredFROMinformation_schema.table_constraintsAStcJOINinformation_schema.key_column_usageASkcuONtc.constraint_name = kcu.constraint_nameJOINinformation_schema.constraint_column_usageASccuONccu.constraint_name = tc.constraint_nameWHEREconstraint_type ='FOREIGN KEY' AND tc.tabl...