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Added ON DELETE/UPDATE SET NULL 

Jan
This commit is contained in:
Jan Wieck 1999-12-06 19:50:49 +00:00
parent b8ef7e7f82
commit 2eb53e684c
1 changed files with 411 additions and 18 deletions
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429
src/backend/utils/adt/ri_triggers.c
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@ -6,7 +6,7 @@
*
* 1999 Jan Wieck
*
* $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.4 1999/12/06 18:02:44 wieck Exp $
* $Header: /cvsroot/pgsql/src/backend/utils/adt/ri_triggers.c,v 1.5 1999/12/06 19:50:49 wieck Exp $
*
* ----------
*/
@ -72,6 +72,8 @@
#define RI_PLAN_CASCADE_UPD_DOUPDATE 1
#define RI_PLAN_RESTRICT_DEL_CHECKREF 1
#define RI_PLAN_RESTRICT_UPD_CHECKREF 1
#define RI_PLAN_SETNULL_DEL_DOUPDATE 1
#define RI_PLAN_SETNULL_UPD_DOUPDATE 1
/* ----------
@ -210,6 +212,10 @@ RI_FKey_check (FmgrInfo *proinfo)
* Gereral rules 2) a):
* If Rf and Rt are empty (no columns to compare given)
* constraint is true if 0 < (SELECT COUNT(*) FROM T)
*
* Note: The special case that no columns are given cannot
* occur up to now in Postgres, it's just there for
* future enhancements.
* ----------
*/
if (tgnargs == 4) {
@ -562,7 +568,7 @@ RI_FKey_cascade_del (FmgrInfo *proinfo)
heap_close(fk_rel, NoLock);
if (SPI_connect() != SPI_OK_CONNECT)
elog(NOTICE, "SPI_connect() failed in RI_FKey_check()");
elog(NOTICE, "SPI_connect() failed in RI_FKey_cascade_del()");
/* ----------
* Fetch or prepare a saved plan for the cascaded delete
@ -714,7 +720,7 @@ RI_FKey_cascade_upd (FmgrInfo *proinfo)
/* ----------
* Get the relation descriptors of the FK and PK tables and
* the old tuple.
* the new and old tuple.
* ----------
*/
fk_rel = heap_openr(tgargs[RI_FK_RELNAME_ARGNO], NoLock);
@ -768,11 +774,11 @@ RI_FKey_cascade_upd (FmgrInfo *proinfo)
return NULL;
if (SPI_connect() != SPI_OK_CONNECT)
elog(NOTICE, "SPI_connect() failed in RI_FKey_restrict_upd()");
elog(NOTICE, "SPI_connect() failed in RI_FKey_cascade_upd()");
/* ----------
* Fetch or prepare a saved plan for the restrict delete
* lookup for foreign references
* Fetch or prepare a saved plan for the cascaded update
* of foreign references
* ----------
*/
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
@ -864,7 +870,7 @@ RI_FKey_cascade_upd (FmgrInfo *proinfo)
return NULL;
/* ----------
* Handle MATCH PARTIAL restrict update.
* Handle MATCH PARTIAL cascade update.
* ----------
*/
case RI_MATCH_TYPE_PARTIAL:
@ -876,7 +882,7 @@ RI_FKey_cascade_upd (FmgrInfo *proinfo)
* Never reached
* ----------
*/
elog(ERROR, "internal error #4 in ri_triggers.c");
elog(ERROR, "internal error #3 in ri_triggers.c");
return NULL;
}
@ -988,7 +994,7 @@ RI_FKey_restrict_del (FmgrInfo *proinfo)
/* ----------
* Fetch or prepare a saved plan for the restrict delete
* lookup for foreign references
* lookup if foreign references exist
* ----------
*/
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
@ -1079,7 +1085,7 @@ RI_FKey_restrict_del (FmgrInfo *proinfo)
* Never reached
* ----------
*/
elog(ERROR, "internal error #3 in ri_triggers.c");
elog(ERROR, "internal error #4 in ri_triggers.c");
return NULL;
}
@ -1143,7 +1149,7 @@ RI_FKey_restrict_upd (FmgrInfo *proinfo)
/* ----------
* Get the relation descriptors of the FK and PK tables and
* the old tuple.
* the new and old tuple.
* ----------
*/
fk_rel = heap_openr(tgargs[RI_FK_RELNAME_ARGNO], NoLock);
@ -1200,8 +1206,8 @@ RI_FKey_restrict_upd (FmgrInfo *proinfo)
elog(NOTICE, "SPI_connect() failed in RI_FKey_restrict_upd()");
/* ----------
* Fetch or prepare a saved plan for the restrict delete
* lookup for foreign references
* Fetch or prepare a saved plan for the restrict update
* lookup if foreign references exist
* ----------
*/
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
@ -1292,7 +1298,7 @@ RI_FKey_restrict_upd (FmgrInfo *proinfo)
* Never reached
* ----------
*/
elog(ERROR, "internal error #4 in ri_triggers.c");
elog(ERROR, "internal error #5 in ri_triggers.c");
return NULL;
}
@ -1306,12 +1312,199 @@ RI_FKey_restrict_upd (FmgrInfo *proinfo)
HeapTuple
RI_FKey_setnull_del (FmgrInfo *proinfo)
{
TriggerData *trigdata;
TriggerData *trigdata;
int tgnargs;
char **tgargs;
Relation fk_rel;
Relation pk_rel;
HeapTuple old_row;
RI_QueryKey qkey;
void *qplan;
Datum upd_values[RI_MAX_NUMKEYS];
char upd_nulls[RI_MAX_NUMKEYS + 1];
bool isnull;
int i;
trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(ERROR, "RI_FKey_setnull_del() called\n");
/* ----------
* Check that this is a valid trigger call on the right time and event.
* ----------
*/
if (trigdata == NULL)
elog(ERROR, "RI_FKey_setnull_del() not fired by trigger manager");
if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
elog(ERROR, "RI_FKey_setnull_del() must be fired AFTER ROW");
if (!TRIGGER_FIRED_BY_DELETE(trigdata->tg_event))
elog(ERROR, "RI_FKey_setnull_del() must be fired for DELETE");
/* ----------
* Check for the correct # of call arguments
* ----------
*/
tgnargs = trigdata->tg_trigger->tgnargs;
tgargs = trigdata->tg_trigger->tgargs;
if (tgnargs < 4 || (tgnargs % 2) != 0)
elog(ERROR, "wrong # of arguments in call to RI_FKey_setnull_del()");
if (tgnargs > RI_MAX_ARGUMENTS)
elog(ERROR, "too many keys (%d max) in call to RI_FKey_setnull_del()",
RI_MAX_NUMKEYS);
/* ----------
* Nothing to do if no column names to compare given
* ----------
*/
if (tgnargs == 4)
return NULL;
/* ----------
* Get the relation descriptors of the FK and PK tables and
* the old tuple.
* ----------
*/
fk_rel = heap_openr(tgargs[RI_FK_RELNAME_ARGNO], NoLock);
pk_rel = trigdata->tg_relation;
old_row = trigdata->tg_trigtuple;
switch (ri_DetermineMatchType(tgargs[RI_MATCH_TYPE_ARGNO]))
{
/* ----------
* SQL3 11.9 <referential constraint definition>
* Gereral rules 6) a) ii):
* MATCH <UNSPECIFIED> or MATCH FULL
* ... ON DELETE SET NULL
* ----------
*/
case RI_MATCH_TYPE_UNSPECIFIED:
case RI_MATCH_TYPE_FULL:
ri_BuildQueryKeyFull(&qkey, trigdata->tg_trigger->tgoid,
RI_PLAN_SETNULL_DEL_DOUPDATE,
fk_rel, pk_rel,
tgnargs, tgargs);
switch (ri_NullCheck(pk_rel, old_row, &qkey, RI_KEYPAIR_PK_IDX))
{
case RI_KEYS_ALL_NULL:
case RI_KEYS_SOME_NULL:
/* ----------
* No update - MATCH FULL means there cannot be any
* reference to old key if it contains NULL
* ----------
*/
heap_close(fk_rel, NoLock);
return NULL;
case RI_KEYS_NONE_NULL:
/* ----------
* Have a full qualified key - continue below
* ----------
*/
break;
}
heap_close(fk_rel, NoLock);
if (SPI_connect() != SPI_OK_CONNECT)
elog(NOTICE, "SPI_connect() failed in RI_FKey_setnull_del()");
/* ----------
* Fetch or prepare a saved plan for the set null delete
* operation
* ----------
*/
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
{
char buf[256];
char querystr[8192];
char qualstr[8192];
char *querysep;
char *qualsep;
Oid queryoids[RI_MAX_NUMKEYS];
/* ----------
* The query string built is
* UPDATE <fktable> SET fkatt1 = NULL [, ...]
* WHERE fkatt1 = $1 [AND ...]
* The type id's for the $ parameters are those of the
* corresponding PK attributes. Thus, SPI_prepare could
* eventually fail if the parser cannot identify some way
* how to compare these two types by '='.
* ----------
*/
sprintf(querystr, "UPDATE \"%s\" SET",
tgargs[RI_FK_RELNAME_ARGNO]);
qualstr[0] = '\0';
querysep = "";
qualsep = "WHERE";
for (i = 0; i < qkey.nkeypairs; i++)
{
sprintf(buf, "%s \"%s\" = NULL", querysep,
tgargs[4 + i * 2]);
strcat(querystr, buf);
sprintf(buf, " %s \"%s\" = $%d", qualsep,
tgargs[4 + i * 2], i + 1);
strcat(qualstr, buf);
querysep = ",";
qualsep = "AND";
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, qualstr);
/* ----------
* Prepare, save and remember the new plan.
* ----------
*/
qplan = SPI_prepare(querystr, qkey.nkeypairs * 2, queryoids);
qplan = SPI_saveplan(qplan);
ri_HashPreparedPlan(&qkey, qplan);
}
/* ----------
* We have a plan now. Build up the arguments for SPI_execp()
* from the key values in the updated PK tuple.
* ----------
*/
for (i = 0; i < qkey.nkeypairs; i++)
{
upd_values[i] = SPI_getbinval(old_row,
pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX],
&isnull);
if (isnull)
upd_nulls[i] = 'n';
else
upd_nulls[i] = ' ';
}
upd_nulls[i] = '\0';
/* ----------
* Now update the existing references
* ----------
*/
if (SPI_execp(qplan, upd_values, upd_nulls, 0) != SPI_OK_UPDATE)
elog(ERROR, "SPI_execp() failed in RI_FKey_setnull_del()");
if (SPI_finish() != SPI_OK_FINISH)
elog(NOTICE, "SPI_finish() failed in RI_FKey_setnull_del()");
return NULL;
/* ----------
* Handle MATCH PARTIAL set null delete.
* ----------
*/
case RI_MATCH_TYPE_PARTIAL:
elog(ERROR, "MATCH PARTIAL not yet supported");
return NULL;
}
/* ----------
* Never reached
* ----------
*/
elog(ERROR, "internal error #6 in ri_triggers.c");
return NULL;
}
@ -1325,12 +1518,212 @@ RI_FKey_setnull_del (FmgrInfo *proinfo)
HeapTuple
RI_FKey_setnull_upd (FmgrInfo *proinfo)
{
TriggerData *trigdata;
TriggerData *trigdata;
int tgnargs;
char **tgargs;
Relation fk_rel;
Relation pk_rel;
HeapTuple new_row;
HeapTuple old_row;
RI_QueryKey qkey;
void *qplan;
Datum upd_values[RI_MAX_NUMKEYS];
char upd_nulls[RI_MAX_NUMKEYS + 1];
bool isnull;
int i;
trigdata = CurrentTriggerData;
CurrentTriggerData = NULL;
elog(ERROR, "RI_FKey_setnull_upd() called\n");
/* ----------
* Check that this is a valid trigger call on the right time and event.
* ----------
*/
if (trigdata == NULL)
elog(ERROR, "RI_FKey_setnull_upd() not fired by trigger manager");
if (!TRIGGER_FIRED_AFTER(trigdata->tg_event) ||
!TRIGGER_FIRED_FOR_ROW(trigdata->tg_event))
elog(ERROR, "RI_FKey_setnull_upd() must be fired AFTER ROW");
if (!TRIGGER_FIRED_BY_UPDATE(trigdata->tg_event))
elog(ERROR, "RI_FKey_setnull_upd() must be fired for UPDATE");
/* ----------
* Check for the correct # of call arguments
* ----------
*/
tgnargs = trigdata->tg_trigger->tgnargs;
tgargs = trigdata->tg_trigger->tgargs;
if (tgnargs < 4 || (tgnargs % 2) != 0)
elog(ERROR, "wrong # of arguments in call to RI_FKey_setnull_upd()");
if (tgnargs > RI_MAX_ARGUMENTS)
elog(ERROR, "too many keys (%d max) in call to RI_FKey_setnull_upd()",
RI_MAX_NUMKEYS);
/* ----------
* Nothing to do if no column names to compare given
* ----------
*/
if (tgnargs == 4)
return NULL;
/* ----------
* Get the relation descriptors of the FK and PK tables and
* the old tuple.
* ----------
*/
fk_rel = heap_openr(tgargs[RI_FK_RELNAME_ARGNO], NoLock);
pk_rel = trigdata->tg_relation;
new_row = trigdata->tg_newtuple;
old_row = trigdata->tg_trigtuple;
switch (ri_DetermineMatchType(tgargs[RI_MATCH_TYPE_ARGNO]))
{
/* ----------
* SQL3 11.9 <referential constraint definition>
* Gereral rules 7) a) ii) 2):
* MATCH FULL
* ... ON UPDATE SET NULL
* ----------
*/
case RI_MATCH_TYPE_UNSPECIFIED:
elog(ERROR, "MATCH UNSPECIFIED not yet supported");
return NULL;
case RI_MATCH_TYPE_FULL:
ri_BuildQueryKeyFull(&qkey, trigdata->tg_trigger->tgoid,
RI_PLAN_SETNULL_UPD_DOUPDATE,
fk_rel, pk_rel,
tgnargs, tgargs);
switch (ri_NullCheck(pk_rel, old_row, &qkey, RI_KEYPAIR_PK_IDX))
{
case RI_KEYS_ALL_NULL:
case RI_KEYS_SOME_NULL:
/* ----------
* No update - MATCH FULL means there cannot be any
* reference to old key if it contains NULL
* ----------
*/
heap_close(fk_rel, NoLock);
return NULL;
case RI_KEYS_NONE_NULL:
/* ----------
* Have a full qualified key - continue below
* ----------
*/
break;
}
heap_close(fk_rel, NoLock);
/* ----------
* No need to do anything if old and new keys are equal
* ----------
*/
if (ri_KeysEqual(pk_rel, old_row, new_row, &qkey,
RI_KEYPAIR_PK_IDX))
return NULL;
if (SPI_connect() != SPI_OK_CONNECT)
elog(NOTICE, "SPI_connect() failed in RI_FKey_setnull_upd()");
/* ----------
* Fetch or prepare a saved plan for the set null update
* operation
* ----------
*/
if ((qplan = ri_FetchPreparedPlan(&qkey)) == NULL)
{
char buf[256];
char querystr[8192];
char qualstr[8192];
char *querysep;
char *qualsep;
Oid queryoids[RI_MAX_NUMKEYS];
/* ----------
* The query string built is
* UPDATE <fktable> SET fkatt1 = NULL [, ...]
* WHERE fkatt1 = $1 [AND ...]
* The type id's for the $ parameters are those of the
* corresponding PK attributes. Thus, SPI_prepare could
* eventually fail if the parser cannot identify some way
* how to compare these two types by '='.
* ----------
*/
sprintf(querystr, "UPDATE \"%s\" SET",
tgargs[RI_FK_RELNAME_ARGNO]);
qualstr[0] = '\0';
querysep = "";
qualsep = "WHERE";
for (i = 0; i < qkey.nkeypairs; i++)
{
sprintf(buf, "%s \"%s\" = NULL", querysep,
tgargs[4 + i * 2]);
strcat(querystr, buf);
sprintf(buf, " %s \"%s\" = $%d", qualsep,
tgargs[4 + i * 2], i + 1);
strcat(qualstr, buf);
querysep = ",";
qualsep = "AND";
queryoids[i] = SPI_gettypeid(pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX]);
}
strcat(querystr, qualstr);
/* ----------
* Prepare, save and remember the new plan.
* ----------
*/
qplan = SPI_prepare(querystr, qkey.nkeypairs * 2, queryoids);
qplan = SPI_saveplan(qplan);
ri_HashPreparedPlan(&qkey, qplan);
}
/* ----------
* We have a plan now. Build up the arguments for SPI_execp()
* from the key values in the updated PK tuple.
* ----------
*/
for (i = 0; i < qkey.nkeypairs; i++)
{
upd_values[i] = SPI_getbinval(old_row,
pk_rel->rd_att,
qkey.keypair[i][RI_KEYPAIR_PK_IDX],
&isnull);
if (isnull)
upd_nulls[i] = 'n';
else
upd_nulls[i] = ' ';
}
upd_nulls[i] = '\0';
/* ----------
* Now update the existing references
* ----------
*/
if (SPI_execp(qplan, upd_values, upd_nulls, 0) != SPI_OK_UPDATE)
elog(ERROR, "SPI_execp() failed in RI_FKey_setnull_upd()");
if (SPI_finish() != SPI_OK_FINISH)
elog(NOTICE, "SPI_finish() failed in RI_FKey_setnull_upd()");
return NULL;
/* ----------
* Handle MATCH PARTIAL set null update.
* ----------
*/
case RI_MATCH_TYPE_PARTIAL:
elog(ERROR, "MATCH PARTIAL not yet supported");
return NULL;
}
/* ----------
* Never reached
* ----------
*/
elog(ERROR, "internal error #7 in ri_triggers.c");
return NULL;
}