Header And Logo
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#include "postgres.h"#include "access/heapam.h"#include "access/xact.h"#include "catalog/namespace.h"#include "commands/defrem.h"#include "commands/tablecmds.h"#include "commands/view.h"#include "miscadmin.h"#include "nodes/makefuncs.h"#include "nodes/nodeFuncs.h"#include "parser/analyze.h"#include "parser/parse_relation.h"#include "rewrite/rewriteDefine.h"#include "rewrite/rewriteManip.h"#include "rewrite/rewriteSupport.h"#include "utils/acl.h"#include "utils/builtins.h"#include "utils/lsyscache.h"#include "utils/rel.h"#include "utils/syscache.h"
Go to the source code of this file.
Functions | |
| static void | checkViewTupleDesc (TupleDesc newdesc, TupleDesc olddesc) |
| static Oid | DefineVirtualRelation (RangeVar *relation, List *tlist, bool replace, List *options) |
| static void | DefineViewRules (Oid viewOid, Query *viewParse, bool replace) |
| static Query * | UpdateRangeTableOfViewParse (Oid viewOid, Query *viewParse) |
| Oid | DefineView (ViewStmt *stmt, const char *queryString) |
| void | StoreViewQuery (Oid viewOid, Query *viewParse, bool replace) |
Definition at line 233 of file view.c.
References tupleDesc::attrs, ereport, errcode(), errmsg(), ERROR, format_type_with_typemod(), i, NameStr, and tupleDesc::natts.
Referenced by DefineVirtualRelation().
{
int i;
if (newdesc->natts < olddesc->natts)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot drop columns from view")));
/* we can ignore tdhasoid */
for (i = 0; i < olddesc->natts; i++)
{
Form_pg_attribute newattr = newdesc->attrs[i];
Form_pg_attribute oldattr = olddesc->attrs[i];
/* XXX msg not right, but we don't support DROP COL on view anyway */
if (newattr->attisdropped != oldattr->attisdropped)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot drop columns from view")));
if (strcmp(NameStr(newattr->attname), NameStr(oldattr->attname)) != 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot change name of view column \"%s\" to \"%s\"",
NameStr(oldattr->attname),
NameStr(newattr->attname))));
/* XXX would it be safe to allow atttypmod to change? Not sure */
if (newattr->atttypid != oldattr->atttypid ||
newattr->atttypmod != oldattr->atttypmod)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("cannot change data type of view column \"%s\" from %s to %s",
NameStr(oldattr->attname),
format_type_with_typemod(oldattr->atttypid,
oldattr->atttypmod),
format_type_with_typemod(newattr->atttypid,
newattr->atttypmod))));
/* We can ignore the remaining attributes of an attribute... */
}
/*
* We ignore the constraint fields. The new view desc can't have any
* constraints, and the only ones that could be on the old view are
* defaults, which we are happy to leave in place.
*/
}
Definition at line 372 of file view.c.
References ViewStmt::aliases, Assert, CMD_SELECT, CommandCounterIncrement(), Query::commandType, copyObject(), DefineVirtualRelation(), elog, ereport, errcode(), errmsg(), ERROR, Query::hasModifyingCTE, IsA, isQueryUsingTempRelation(), lfirst, list_head(), lnext, NIL, NOTICE, NULL, ViewStmt::options, parse_analyze(), pstrdup(), ViewStmt::query, RangeVar::relname, RangeVar::relpersistence, RELPERSISTENCE_PERMANENT, RELPERSISTENCE_UNLOGGED, ViewStmt::replace, TargetEntry::resjunk, TargetEntry::resname, StoreViewQuery(), strVal, Query::targetList, Query::utilityStmt, and ViewStmt::view.
Referenced by ProcessUtilitySlow().
{
Query *viewParse;
Oid viewOid;
RangeVar *view;
/*
* Run parse analysis to convert the raw parse tree to a Query. Note this
* also acquires sufficient locks on the source table(s).
*
* Since parse analysis scribbles on its input, copy the raw parse tree;
* this ensures we don't corrupt a prepared statement, for example.
*/
viewParse = parse_analyze((Node *) copyObject(stmt->query),
queryString, NULL, 0);
/*
* The grammar should ensure that the result is a single SELECT Query.
* However, it doesn't forbid SELECT INTO, so we have to check for that.
*/
if (!IsA(viewParse, Query))
elog(ERROR, "unexpected parse analysis result");
if (viewParse->utilityStmt != NULL &&
IsA(viewParse->utilityStmt, CreateTableAsStmt))
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("views must not contain SELECT INTO")));
if (viewParse->commandType != CMD_SELECT ||
viewParse->utilityStmt != NULL)
elog(ERROR, "unexpected parse analysis result");
/*
* Check for unsupported cases. These tests are redundant with ones in
* DefineQueryRewrite(), but that function will complain about a bogus ON
* SELECT rule, and we'd rather the message complain about a view.
*/
if (viewParse->hasModifyingCTE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("views must not contain data-modifying statements in WITH")));
/*
* If a list of column names was given, run through and insert these into
* the actual query tree. - thomas 2000-03-08
*/
if (stmt->aliases != NIL)
{
ListCell *alist_item = list_head(stmt->aliases);
ListCell *targetList;
foreach(targetList, viewParse->targetList)
{
TargetEntry *te = (TargetEntry *) lfirst(targetList);
Assert(IsA(te, TargetEntry));
/* junk columns don't get aliases */
if (te->resjunk)
continue;
te->resname = pstrdup(strVal(lfirst(alist_item)));
alist_item = lnext(alist_item);
if (alist_item == NULL)
break; /* done assigning aliases */
}
if (alist_item != NULL)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("CREATE VIEW specifies more column "
"names than columns")));
}
/* Unlogged views are not sensible. */
if (stmt->view->relpersistence == RELPERSISTENCE_UNLOGGED)
ereport(ERROR,
(errcode(ERRCODE_SYNTAX_ERROR),
errmsg("views cannot be unlogged because they do not have storage")));
/*
* If the user didn't explicitly ask for a temporary view, check whether
* we need one implicitly. We allow TEMP to be inserted automatically as
* long as the CREATE command is consistent with that --- no explicit
* schema name.
*/
view = copyObject(stmt->view); /* don't corrupt original command */
if (view->relpersistence == RELPERSISTENCE_PERMANENT
&& isQueryUsingTempRelation(viewParse))
{
view->relpersistence = RELPERSISTENCE_TEMP;
ereport(NOTICE,
(errmsg("view \"%s\" will be a temporary view",
view->relname)));
}
/*
* Create the view relation
*
* NOTE: if it already exists and replace is false, the xact will be
* aborted.
*/
viewOid = DefineVirtualRelation(view, viewParse->targetList,
stmt->replace, stmt->options);
/*
* The relation we have just created is not visible to any other commands
* running with the same transaction & command id. So, increment the
* command id counter (but do NOT pfree any memory!!!!)
*/
CommandCounterIncrement();
StoreViewQuery(viewOid, viewParse, stmt->replace);
return viewOid;
}
Definition at line 282 of file view.c.
References CMD_SELECT, DefineQueryRewrite(), list_make1, NULL, pstrdup(), and ViewSelectRuleName.
Referenced by StoreViewQuery().
{
/*
* Set up the ON SELECT rule. Since the query has already been through
* parse analysis, we use DefineQueryRewrite() directly.
*/
DefineQueryRewrite(pstrdup(ViewSelectRuleName),
viewOid,
NULL,
CMD_SELECT,
true,
replace,
list_make1(viewParse));
/*
* Someday: automatic ON INSERT, etc
*/
}
| static Oid DefineVirtualRelation | ( | RangeVar * | relation, | |
| List * | tlist, | |||
| bool | replace, | |||
| List * | options | |||
| ) | [static] |
Definition at line 50 of file view.c.
References AccessExclusiveLock, AlterTableInternal(), Assert, BuildDescForRelation(), CheckTableNotInUse(), checkViewTupleDesc(), ColumnDef::collClause, ColumnDef::collOid, ColumnDef::colname, CreateStmt::constraints, ColumnDef::constraints, ColumnDef::cooked_default, AlterTableCmd::def, DefineRelation(), ereport, errcode(), errhint(), errmsg(), ERROR, TargetEntry::expr, exprCollation(), exprType(), exprTypmod(), CreateStmt::if_not_exists, ColumnDef::inhcount, CreateStmt::inhRelations, InvalidOid, ColumnDef::is_from_type, ColumnDef::is_local, ColumnDef::is_not_null, lappend(), lfirst, list_length(), makeNode, makeTypeNameFromOid(), tupleDesc::natts, NIL, NoLock, OidIsValid, CreateStmt::oncommit, CreateStmt::options, pstrdup(), RangeVarGetAndCheckCreationNamespace(), ColumnDef::raw_default, RelationData::rd_att, RelationData::rd_rel, CreateStmt::relation, relation_close(), relation_open(), RelationGetRelationName, RELKIND_VIEW, RangeVar::relpersistence, TargetEntry::resjunk, TargetEntry::resname, skip(), ColumnDef::storage, AlterTableCmd::subtype, CreateStmt::tableElts, CreateStmt::tablespacename, type_is_collatable(), and ColumnDef::typeName.
Referenced by DefineView().
{
Oid viewOid;
LOCKMODE lockmode;
CreateStmt *createStmt = makeNode(CreateStmt);
List *attrList;
ListCell *t;
/*
* create a list of ColumnDef nodes based on the names and types of the
* (non-junk) targetlist items from the view's SELECT list.
*/
attrList = NIL;
foreach(t, tlist)
{
TargetEntry *tle = lfirst(t);
if (!tle->resjunk)
{
ColumnDef *def = makeNode(ColumnDef);
def->colname = pstrdup(tle->resname);
def->typeName = makeTypeNameFromOid(exprType((Node *) tle->expr),
exprTypmod((Node *) tle->expr));
def->inhcount = 0;
def->is_local = true;
def->is_not_null = false;
def->is_from_type = false;
def->storage = 0;
def->raw_default = NULL;
def->cooked_default = NULL;
def->collClause = NULL;
def->collOid = exprCollation((Node *) tle->expr);
/*
* It's possible that the column is of a collatable type but the
* collation could not be resolved, so double-check.
*/
if (type_is_collatable(exprType((Node *) tle->expr)))
{
if (!OidIsValid(def->collOid))
ereport(ERROR,
(errcode(ERRCODE_INDETERMINATE_COLLATION),
errmsg("could not determine which collation to use for view column \"%s\"",
def->colname),
errhint("Use the COLLATE clause to set the collation explicitly.")));
}
else
Assert(!OidIsValid(def->collOid));
def->constraints = NIL;
attrList = lappend(attrList, def);
}
}
if (attrList == NIL)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TABLE_DEFINITION),
errmsg("view must have at least one column")));
/*
* Look up, check permissions on, and lock the creation namespace; also
* check for a preexisting view with the same name. This will also set
* relation->relpersistence to RELPERSISTENCE_TEMP if the selected
* namespace is temporary.
*/
lockmode = replace ? AccessExclusiveLock : NoLock;
(void) RangeVarGetAndCheckCreationNamespace(relation, lockmode, &viewOid);
if (OidIsValid(viewOid) && replace)
{
Relation rel;
TupleDesc descriptor;
List *atcmds = NIL;
AlterTableCmd *atcmd;
/* Relation is already locked, but we must build a relcache entry. */
rel = relation_open(viewOid, NoLock);
/* Make sure it *is* a view. */
if (rel->rd_rel->relkind != RELKIND_VIEW)
ereport(ERROR,
(errcode(ERRCODE_WRONG_OBJECT_TYPE),
errmsg("\"%s\" is not a view",
RelationGetRelationName(rel))));
/* Also check it's not in use already */
CheckTableNotInUse(rel, "CREATE OR REPLACE VIEW");
/*
* Due to the namespace visibility rules for temporary objects, we
* should only end up replacing a temporary view with another
* temporary view, and similarly for permanent views.
*/
Assert(relation->relpersistence == rel->rd_rel->relpersistence);
/*
* Create a tuple descriptor to compare against the existing view, and
* verify that the old column list is an initial prefix of the new
* column list.
*/
descriptor = BuildDescForRelation(attrList);
checkViewTupleDesc(descriptor, rel->rd_att);
/*
* The new options list replaces the existing options list, even if
* it's empty.
*/
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_ReplaceRelOptions;
atcmd->def = (Node *) options;
atcmds = lappend(atcmds, atcmd);
/*
* If new attributes have been added, we must add pg_attribute entries
* for them. It is convenient (although overkill) to use the ALTER
* TABLE ADD COLUMN infrastructure for this.
*/
if (list_length(attrList) > rel->rd_att->natts)
{
ListCell *c;
int skip = rel->rd_att->natts;
foreach(c, attrList)
{
if (skip > 0)
{
skip--;
continue;
}
atcmd = makeNode(AlterTableCmd);
atcmd->subtype = AT_AddColumnToView;
atcmd->def = (Node *) lfirst(c);
atcmds = lappend(atcmds, atcmd);
}
}
/* OK, let's do it. */
AlterTableInternal(viewOid, atcmds, true);
/*
* Seems okay, so return the OID of the pre-existing view.
*/
relation_close(rel, NoLock); /* keep the lock! */
return viewOid;
}
else
{
Oid relid;
/*
* now set the parameters for keys/inheritance etc. All of these are
* uninteresting for views...
*/
createStmt->relation = relation;
createStmt->tableElts = attrList;
createStmt->inhRelations = NIL;
createStmt->constraints = NIL;
createStmt->options = options;
createStmt->oncommit = ONCOMMIT_NOOP;
createStmt->tablespacename = NULL;
createStmt->if_not_exists = false;
/*
* finally create the relation (this will error out if there's an
* existing view, so we don't need more code to complain if "replace"
* is false).
*/
relid = DefineRelation(createStmt, RELKIND_VIEW, InvalidOid);
Assert(relid != InvalidOid);
return relid;
}
}
Definition at line 490 of file view.c.
References DefineViewRules(), and UpdateRangeTableOfViewParse().
Referenced by DefineView(), and intorel_startup().
{
/*
* The range table of 'viewParse' does not contain entries for the "OLD"
* and "NEW" relations. So... add them!
*/
viewParse = UpdateRangeTableOfViewParse(viewOid, viewParse);
/*
* Now create the rules associated with the view.
*/
DefineViewRules(viewOid, viewParse, replace);
}
Definition at line 319 of file view.c.
References AccessShareLock, addRangeTableEntryForRelation(), copyObject(), lcons(), makeAlias(), NIL, NULL, OffsetVarNodes(), relation_close(), relation_open(), RangeTblEntry::requiredPerms, and Query::rtable.
Referenced by StoreViewQuery().
{
Relation viewRel;
List *new_rt;
RangeTblEntry *rt_entry1,
*rt_entry2;
/*
* Make a copy of the given parsetree. It's not so much that we don't
* want to scribble on our input, it's that the parser has a bad habit of
* outputting multiple links to the same subtree for constructs like
* BETWEEN, and we mustn't have OffsetVarNodes increment the varno of a
* Var node twice. copyObject will expand any multiply-referenced subtree
* into multiple copies.
*/
viewParse = (Query *) copyObject(viewParse);
/* need to open the rel for addRangeTableEntryForRelation */
viewRel = relation_open(viewOid, AccessShareLock);
/*
* Create the 2 new range table entries and form the new range table...
* OLD first, then NEW....
*/
rt_entry1 = addRangeTableEntryForRelation(NULL, viewRel,
makeAlias("old", NIL),
false, false);
rt_entry2 = addRangeTableEntryForRelation(NULL, viewRel,
makeAlias("new", NIL),
false, false);
/* Must override addRangeTableEntry's default access-check flags */
rt_entry1->requiredPerms = 0;
rt_entry2->requiredPerms = 0;
new_rt = lcons(rt_entry1, lcons(rt_entry2, viewParse->rtable));
viewParse->rtable = new_rt;
/*
* Now offset all var nodes by 2, and jointree RT indexes too.
*/
OffsetVarNodes((Node *) viewParse, 2, 0);
relation_close(viewRel, AccessShareLock);
return viewParse;
}
1.7.1