open-dsi
/
postgres
mirror of https://github.com/postgres/postgres
1
0
Fork 0
Code Issues Packages Projects Releases Wiki Activity

Fix ALTER TABLE to check pre-existing NOT NULL constraints when rewriting

Browse Source 
a table.  Otherwise a USING clause that yields NULL can leave the table
violating its constraint (possibly there are other cases too).  Per report
from Alexander Pravking.
REL8_2_STABLE
Tom Lane 19 years ago
parent c5133e5920
commit cb33de773d
1 changed files with 38 additions and 31 deletions
Show all changes Ignore whitespace when comparing lines Ignore changes in amount of whitespace Ignore changes in whitespace at EOL
Show Stats Download Patch File Download Diff File
  1. 69
      src/backend/commands/tablecmds.c

69
src/backend/commands/tablecmds.c
Unescape View File

@ -8,7 +8,7 @@
*
*
* IDENTIFICATION
* $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.192 2006/07/03 22:45:38 tgl Exp $
* $PostgreSQL: pgsql/src/backend/commands/tablecmds.c,v 1.193 2006/07/10 22:10:39 tgl Exp $
*
*-------------------------------------------------------------------------
*/
@ -123,6 +123,7 @@ typedef struct AlteredTableInfo
/* Information saved by Phases 1/2 for Phase 3: */
List *constraints; /* List of NewConstraint */
List *newvals; /* List of NewColumnValue */
bool new_notnull; /* T if we added new NOT NULL constraints */
Oid newTableSpace; /* new tablespace; 0 means no change */
/* Objects to rebuild after completing ALTER TYPE operations */
List *changedConstraintOids; /* OIDs of constraints to rebuild */
@ -132,11 +133,11 @@ typedef struct AlteredTableInfo
} AlteredTableInfo;
/* Struct describing one new constraint to check in Phase 3 scan */
/* Note: new NOT NULL constraints are handled elsewhere */
typedef struct NewConstraint
{
char *name; /* Constraint name, or NULL if none */
ConstrType contype; /* CHECK, NOT_NULL, or FOREIGN */
AttrNumber attnum; /* only relevant for NOT_NULL */
ConstrType contype; /* CHECK or FOREIGN */
Oid refrelid; /* PK rel, if FOREIGN */
Node *qual; /* Check expr or FkConstraint struct */
List *qualstate; /* Execution state for CHECK */
@ -2438,7 +2439,7 @@ ATRewriteTables(List **wqueue)
* Test the current data within the table against new constraints
* generated by ALTER TABLE commands, but don't rebuild data.
*/
if (tab->constraints != NIL)
if (tab->constraints != NIL || tab->new_notnull)
ATRewriteTable(tab, InvalidOid);
/*
@ -2504,6 +2505,7 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
TupleDesc oldTupDesc;
TupleDesc newTupDesc;
bool needscan = false;
List *notnull_attrs;
int i;
ListCell *l;
EState *estate;
@ -2554,9 +2556,6 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
case CONSTR_FOREIGN:
/* Nothing to do here */
break;
case CONSTR_NOTNULL:
needscan = true;
break;
default:
elog(ERROR, "unrecognized constraint type: %d",
(int) con->contype);
@ -2572,6 +2571,25 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
ex->exprstate = ExecPrepareExpr((Expr *) ex->expr, estate);
}
notnull_attrs = NIL;
if (newrel || tab->new_notnull)
{
/*
* If we are rebuilding the tuples OR if we added any new NOT NULL
* constraints, check all not-null constraints. This is a bit of
* overkill but it minimizes risk of bugs, and heap_attisnull is
* a pretty cheap test anyway.
*/
for (i = 0; i < newTupDesc->natts; i++)
{
if (newTupDesc->attrs[i]->attnotnull &&
!newTupDesc->attrs[i]->attisdropped)
notnull_attrs = lappend_int(notnull_attrs, i);
}
if (notnull_attrs)
needscan = true;
}
if (needscan)
{
ExprContext *econtext;
@ -2672,6 +2690,17 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
ExecStoreTuple(tuple, newslot, InvalidBuffer, false);
econtext->ecxt_scantuple = newslot;
foreach(l, notnull_attrs)
{
int attn = lfirst_int(l);
if (heap_attisnull(tuple, attn+1))
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("column \"%s\" contains null values",
NameStr(newTupDesc->attrs[attn]->attname))));
}
foreach(l, tab->constraints)
{
NewConstraint *con = lfirst(l);
@ -2685,21 +2714,6 @@ ATRewriteTable(AlteredTableInfo *tab, Oid OIDNewHeap)
errmsg("check constraint \"%s\" is violated by some row",
con->name)));
break;
case CONSTR_NOTNULL:
{
Datum d;
bool isnull;
d = heap_getattr(tuple, con->attnum, newTupDesc,
&isnull);
if (isnull)
ereport(ERROR,
(errcode(ERRCODE_NOT_NULL_VIOLATION),
errmsg("column \"%s\" contains null values",
get_attname(tab->relid,
con->attnum))));
}
break;
case CONSTR_FOREIGN:
/* Nothing to do here */
break;
@ -3398,7 +3412,6 @@ ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
HeapTuple tuple;
AttrNumber attnum;
Relation attr_rel;
NewConstraint *newcon;
/*
* lookup the attribute
@ -3434,13 +3447,8 @@ ATExecSetNotNull(AlteredTableInfo *tab, Relation rel,
/* keep the system catalog indexes current */
CatalogUpdateIndexes(attr_rel, tuple);
/* Tell Phase 3 to test the constraint */
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
newcon->contype = CONSTR_NOTNULL;
newcon->attnum = attnum;
newcon->name = "NOT NULL";
tab->constraints = lappend(tab->constraints, newcon);
/* Tell Phase 3 it needs to test the constraint */
tab->new_notnull = true;
}
heap_close(attr_rel, RowExclusiveLock);
@ -3909,7 +3917,6 @@ ATExecAddConstraint(AlteredTableInfo *tab, Relation rel, Node *newConstraint)
newcon = (NewConstraint *) palloc0(sizeof(NewConstraint));
newcon->name = ccon->name;
newcon->contype = ccon->contype;
newcon->attnum = ccon->attnum;
/* ExecQual wants implicit-AND format */
newcon->qual = (Node *)
make_ands_implicit((Expr *) ccon->expr);

Write Preview
Loading…
Cancel
Save