diff options
Diffstat (limited to 'src/backend/parser/parse_utilcmd.c')
| -rw-r--r-- | src/backend/parser/parse_utilcmd.c | 206 |
1 files changed, 55 insertions, 151 deletions
diff --git a/src/backend/parser/parse_utilcmd.c b/src/backend/parser/parse_utilcmd.c index ea0fe6f8116..b0f6fe4fa61 100644 --- a/src/backend/parser/parse_utilcmd.c +++ b/src/backend/parser/parse_utilcmd.c @@ -83,7 +83,6 @@ typedef struct List *ckconstraints; /* CHECK constraints */ List *fkconstraints; /* FOREIGN KEY constraints */ List *ixconstraints; /* index-creating constraints */ - List *nnconstraints; /* NOT NULL constraints */ List *likeclauses; /* LIKE clauses that need post-processing */ List *extstats; /* cloned extended statistics */ List *blist; /* "before list" of things to do before @@ -245,7 +244,6 @@ transformCreateStmt(CreateStmt *stmt, const char *queryString) cxt.ckconstraints = NIL; cxt.fkconstraints = NIL; cxt.ixconstraints = NIL; - cxt.nnconstraints = NIL; cxt.likeclauses = NIL; cxt.extstats = NIL; cxt.blist = NIL; @@ -350,7 +348,6 @@ transformCreateStmt(CreateStmt *stmt, const char *queryString) */ stmt->tableElts = cxt.columns; stmt->constraints = cxt.ckconstraints; - stmt->nnconstraints = cxt.nnconstraints; result = lappend(cxt.blist, stmt); result = list_concat(result, cxt.alist); @@ -540,7 +537,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) bool saw_default; bool saw_identity; bool saw_generated; - bool need_notnull = false; ListCell *clist; cxt->columns = lappend(cxt->columns, column); @@ -638,8 +634,10 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) constraint->cooked_expr = NULL; column->constraints = lappend(column->constraints, constraint); - /* have a NOT NULL constraint added later */ - need_notnull = true; + constraint = makeNode(Constraint); + constraint->contype = CONSTR_NOTNULL; + constraint->location = -1; + column->constraints = lappend(column->constraints, constraint); } /* Process column constraints, if any... */ @@ -657,7 +655,7 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) switch (constraint->contype) { case CONSTR_NULL: - if ((saw_nullable && column->is_not_null) || need_notnull) + if (saw_nullable && column->is_not_null) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"", @@ -669,58 +667,15 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) break; case CONSTR_NOTNULL: - - /* - * For NOT NULL declarations, we need to mark the column as - * not nullable, and set things up to have a CHECK constraint - * created. Also, duplicate NOT NULL declarations are not - * allowed. - */ - if (saw_nullable) - { - if (!column->is_not_null) - ereport(ERROR, - (errcode(ERRCODE_SYNTAX_ERROR), - errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"", - column->colname, cxt->relation->relname), - parser_errposition(cxt->pstate, - constraint->location))); - else - ereport(ERROR, - errcode(ERRCODE_SYNTAX_ERROR), - errmsg("redundant NOT NULL declarations for column \"%s\" of table \"%s\"", - column->colname, cxt->relation->relname), - parser_errposition(cxt->pstate, - constraint->location)); - } - - /* - * If this is the first time we see this column being marked - * not null, keep track to later add a NOT NULL constraint. - */ - if (!column->is_not_null) - { - Constraint *notnull; - - column->is_not_null = true; - saw_nullable = true; - - notnull = makeNode(Constraint); - notnull->contype = CONSTR_NOTNULL; - notnull->conname = constraint->conname; - notnull->deferrable = false; - notnull->initdeferred = false; - notnull->location = -1; - notnull->colname = column->colname; - notnull->skip_validation = false; - notnull->initially_valid = true; - - cxt->nnconstraints = lappend(cxt->nnconstraints, notnull); - - /* Don't need this anymore, if we had it */ - need_notnull = false; - } - + if (saw_nullable && !column->is_not_null) + ereport(ERROR, + (errcode(ERRCODE_SYNTAX_ERROR), + errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"", + column->colname, cxt->relation->relname), + parser_errposition(cxt->pstate, + constraint->location))); + column->is_not_null = true; + saw_nullable = true; break; case CONSTR_DEFAULT: @@ -770,19 +725,16 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) column->identity = constraint->generated_when; saw_identity = true; - /* - * Identity columns are always NOT NULL, but we may have a - * constraint already. - */ - if (!saw_nullable) - need_notnull = true; - else if (!column->is_not_null) + /* An identity column is implicitly NOT NULL */ + if (saw_nullable && !column->is_not_null) ereport(ERROR, (errcode(ERRCODE_SYNTAX_ERROR), errmsg("conflicting NULL/NOT NULL declarations for column \"%s\" of table \"%s\"", column->colname, cxt->relation->relname), parser_errposition(cxt->pstate, constraint->location))); + column->is_not_null = true; + saw_nullable = true; break; } @@ -806,11 +758,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) case CONSTR_CHECK: cxt->ckconstraints = lappend(cxt->ckconstraints, constraint); - - /* - * XXX If the user says CHECK (IS NOT NULL), should we turn - * that into a regular NOT NULL constraint? - */ break; case CONSTR_PRIMARY: @@ -894,29 +841,6 @@ transformColumnDefinition(CreateStmtContext *cxt, ColumnDef *column) } /* - * If we need a NOT NULL constraint for SERIAL or IDENTITY, and one was - * not explicitly specified, add one now. - */ - if (need_notnull && !(saw_nullable && column->is_not_null)) - { - Constraint *notnull; - - column->is_not_null = true; - - notnull = makeNode(Constraint); - notnull->contype = CONSTR_NOTNULL; - notnull->conname = NULL; - notnull->deferrable = false; - notnull->initdeferred = false; - notnull->location = -1; - notnull->colname = column->colname; - notnull->skip_validation = false; - notnull->initially_valid = true; - - cxt->nnconstraints = lappend(cxt->nnconstraints, notnull); - } - - /* * If needed, generate ALTER FOREIGN TABLE ALTER COLUMN statement to add * per-column foreign data wrapper options to this column after creation. */ @@ -991,10 +915,6 @@ transformTableConstraint(CreateStmtContext *cxt, Constraint *constraint) cxt->ckconstraints = lappend(cxt->ckconstraints, constraint); break; - case CONSTR_NOTNULL: - cxt->nnconstraints = lappend(cxt->nnconstraints, constraint); - break; - case CONSTR_FOREIGN: if (cxt->isforeign) ereport(ERROR, @@ -1006,6 +926,7 @@ transformTableConstraint(CreateStmtContext *cxt, Constraint *constraint) break; case CONSTR_NULL: + case CONSTR_NOTNULL: case CONSTR_DEFAULT: case CONSTR_ATTR_DEFERRABLE: case CONSTR_ATTR_NOT_DEFERRABLE: @@ -1041,7 +962,6 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla AclResult aclresult; char *comment; ParseCallbackState pcbstate; - bool process_notnull_constraints = false; setup_parser_errposition_callback(&pcbstate, cxt->pstate, table_like_clause->relation->location); @@ -1123,8 +1043,6 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla def->inhcount = 0; def->is_local = true; def->is_not_null = attribute->attnotnull; - if (attribute->attnotnull) - process_notnull_constraints = true; def->is_from_type = false; def->storage = 0; def->raw_default = NULL; @@ -1206,19 +1124,14 @@ transformTableLikeClause(CreateStmtContext *cxt, TableLikeClause *table_like_cla * we don't yet know what column numbers the copied columns will have in * the finished table. If any of those options are specified, add the * LIKE clause to cxt->likeclauses so that expandTableLikeClause will be - * called after we do know that; in addition, do that if there are any NOT - * NULL constraints, because those must be propagated even if not - * explicitly requested. - * - * In order for this to work, we remember the relation OID so that + * called after we do know that. Also, remember the relation OID so that * expandTableLikeClause is certain to open the same table. */ - if ((table_like_clause->options & + if (table_like_clause->options & (CREATE_TABLE_LIKE_DEFAULTS | CREATE_TABLE_LIKE_GENERATED | CREATE_TABLE_LIKE_CONSTRAINTS | - CREATE_TABLE_LIKE_INDEXES)) || - process_notnull_constraints) + CREATE_TABLE_LIKE_INDEXES)) { table_like_clause->relationOid = RelationGetRelid(relation); cxt->likeclauses = lappend(cxt->likeclauses, table_like_clause); @@ -1290,7 +1203,6 @@ expandTableLikeClause(RangeVar *heapRel, TableLikeClause *table_like_clause) TupleConstr *constr; AttrMap *attmap; char *comment; - ListCell *lc; /* * Open the relation referenced by the LIKE clause. We should still have @@ -1471,20 +1383,6 @@ expandTableLikeClause(RangeVar *heapRel, TableLikeClause *table_like_clause) } /* - * Copy NOT NULL constraints, too (these do not require any option to have - * been given). - */ - foreach(lc, RelationGetNotNullConstraints(relation, false)) - { - AlterTableCmd *atsubcmd; - - atsubcmd = makeNode(AlterTableCmd); - atsubcmd->subtype = AT_AddConstraint; - atsubcmd->def = (Node *) lfirst_node(Constraint, lc); - atsubcmds = lappend(atsubcmds, atsubcmd); - } - - /* * If we generated any ALTER TABLE actions above, wrap them into a single * ALTER TABLE command. Stick it at the front of the result, so it runs * before any CommentStmts we made above. @@ -2161,12 +2059,10 @@ transformIndexConstraints(CreateStmtContext *cxt) ListCell *lc; /* - * Run through the constraints that need to generate an index, and do so. - * - * For PRIMARY KEY, in addition we set each column's attnotnull flag true. - * We do not create a separate CHECK (IS NOT NULL) constraint, as that - * would be redundant: the PRIMARY KEY constraint itself fulfills that - * role. Other constraint types don't need any NOT NULL markings. + * Run through the constraints that need to generate an index. For PRIMARY + * KEY, mark each column as NOT NULL and create an index. For UNIQUE or + * EXCLUDE, create an index as for PRIMARY KEY, but do not insist on NOT + * NULL. */ foreach(lc, cxt->ixconstraints) { @@ -2240,7 +2136,9 @@ transformIndexConstraints(CreateStmtContext *cxt) } /* - * Now append all the IndexStmts to cxt->alist. + * Now append all the IndexStmts to cxt->alist. If we generated an ALTER + * TABLE SET NOT NULL statement to support a primary key, it's already in + * cxt->alist. */ cxt->alist = list_concat(cxt->alist, finalindexlist); } @@ -2248,10 +2146,12 @@ transformIndexConstraints(CreateStmtContext *cxt) /* * transformIndexConstraint * Transform one UNIQUE, PRIMARY KEY, or EXCLUDE constraint for - * transformIndexConstraints. An IndexStmt is returned. + * transformIndexConstraints. * - * For a PRIMARY KEY constraint, we additionally force the columns to be - * marked as NOT NULL, without producing a CHECK (IS NOT NULL) constraint. + * We return an IndexStmt. For a PRIMARY KEY constraint, we additionally + * produce NOT NULL constraints, either by marking ColumnDefs in cxt->columns + * as is_not_null or by adding an ALTER TABLE SET NOT NULL command to + * cxt->alist. */ static IndexStmt * transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt) @@ -2517,6 +2417,7 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt) { char *key = strVal(lfirst(lc)); bool found = false; + bool forced_not_null = false; ColumnDef *column = NULL; ListCell *columns; IndexElem *iparam; @@ -2537,14 +2438,13 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt) * column is defined in the new table. For PRIMARY KEY, we * can apply the NOT NULL constraint cheaply here ... unless * the column is marked is_from_type, in which case marking it - * here would be ineffective (see MergeAttributes). Note that - * this isn't effective in ALTER TABLE either, unless the - * column is being added in the same command. + * here would be ineffective (see MergeAttributes). */ if (constraint->contype == CONSTR_PRIMARY && !column->is_from_type) { column->is_not_null = true; + forced_not_null = true; } } else if (SystemAttributeByName(key) != NULL) @@ -2587,6 +2487,14 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt) if (strcmp(key, inhname) == 0) { found = true; + + /* + * It's tempting to set forced_not_null if the + * parent column is already NOT NULL, but that + * seems unsafe because the column's NOT NULL + * marking might disappear between now and + * execution. Do the runtime check to be safe. + */ break; } } @@ -2640,11 +2548,15 @@ transformIndexConstraint(Constraint *constraint, CreateStmtContext *cxt) iparam->nulls_ordering = SORTBY_NULLS_DEFAULT; index->indexParams = lappend(index->indexParams, iparam); - if (constraint->contype == CONSTR_PRIMARY) + /* + * For a primary-key column, also create an item for ALTER TABLE + * SET NOT NULL if we couldn't ensure it via is_not_null above. + */ + if (constraint->contype == CONSTR_PRIMARY && !forced_not_null) { AlterTableCmd *notnullcmd = makeNode(AlterTableCmd); - notnullcmd->subtype = AT_SetAttNotNull; + notnullcmd->subtype = AT_SetNotNull; notnullcmd->name = pstrdup(key); notnullcmds = lappend(notnullcmds, notnullcmd); } @@ -3416,7 +3328,6 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, cxt.isalter = true; cxt.columns = NIL; cxt.ckconstraints = NIL; - cxt.nnconstraints = NIL; cxt.fkconstraints = NIL; cxt.ixconstraints = NIL; cxt.likeclauses = NIL; @@ -3660,8 +3571,8 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, /* * We assume here that cxt.alist contains only IndexStmts and possibly - * AT_SetAttNotNull statements generated from primary key constraints. - * We absorb the subcommands of the latter directly. + * ALTER TABLE SET NOT NULL statements generated from primary key + * constraints. We absorb the subcommands of the latter directly. */ if (IsA(istmt, IndexStmt)) { @@ -3689,21 +3600,14 @@ transformAlterTableStmt(Oid relid, AlterTableStmt *stmt, { newcmd = makeNode(AlterTableCmd); newcmd->subtype = AT_AddConstraint; - newcmd->def = (Node *) lfirst_node(Constraint, l); + newcmd->def = (Node *) lfirst(l); newcmds = lappend(newcmds, newcmd); } foreach(l, cxt.fkconstraints) { newcmd = makeNode(AlterTableCmd); newcmd->subtype = AT_AddConstraint; - newcmd->def = (Node *) lfirst_node(Constraint, l); - newcmds = lappend(newcmds, newcmd); - } - foreach(l, cxt.nnconstraints) - { - newcmd = makeNode(AlterTableCmd); - newcmd->subtype = AT_AddConstraint; - newcmd->def = (Node *) lfirst_node(Constraint, l); + newcmd->def = (Node *) lfirst(l); newcmds = lappend(newcmds, newcmd); } |