errmsg("\"%s\" is not a table",

RelationGetRelationName(rel))));

if (tab->relkind == RELKIND_COMPOSITE_TYPE ||

tab->relkind == RELKIND_FOREIGN_TABLE)

if (!RELKIND_HAS_STORAGE(tab->relkind))

{

/*

* Forcomposite types, do this check now.Tables will check it later

* when the table is being rewritten.

* Forrelations without storage, do this check now.Regular tables

*will check it laterwhen the table is being rewritten.

*/

find_composite_type_dependencies(rel->rd_rel->reltype, rel, NULL);

}

(3 rows)

drop table another;

-- table's row type

create table tab1 (a int, b text);

create table tab2 (x int, y tab1);

alter table tab1 alter column b type varchar; -- fails

ERROR: cannot alter table "tab1" because column "tab2.y" uses its row type

-- We disallow changing table's row type if it's used for storage

create table at_tab1 (a int, b text);

create table at_tab2 (x int, y at_tab1);

alter table at_tab1 alter column b type varchar; -- fails

ERROR: cannot alter table "at_tab1" because column "at_tab2.y" uses its row type

drop table at_tab2;

-- Use of row type in an expression is defended differently

create table at_tab2 (x int, y text, check((x,y)::at_tab1 = (1,'42')::at_tab1));

alter table at_tab1 alter column b type varchar; -- allowed, but ...

insert into at_tab2 values(1,'42'); -- ... this will fail

ERROR: ROW() column has type text instead of type character varying

drop table at_tab1, at_tab2;

-- Check it for a partitioned table, too

create table at_tab1 (a int, b text) partition by list(a);

create table at_tab2 (x int, y at_tab1);

alter table at_tab1 alter column b type varchar; -- fails

ERROR: cannot alter table "at_tab1" because column "at_tab2.y" uses its row type

drop table at_tab1, at_tab2;

-- Alter column type that's part of a partitioned index

create table at_partitioned (a int, b text) partition by range (a);

create table at_part_1 partition of at_partitioned for values from (0) to (1000);

droptable another;

createtabletab1 (aint, btext);

createtabletab2 (xint, y tab1);

altertable tab1 alter column b typevarchar;-- fails

createtableat_tab1 (aint, btext);

createtableat_tab2 (xint, y at_tab1);

altertable at_tab1 alter column b typevarchar;-- fails

droptable at_tab2;

createtableat_tab2 (xint, ytext,check((x,y)::at_tab1= (1,'42')::at_tab1));

altertable at_tab1 alter column b typevarchar;-- allowed, but ...

insert into at_tab2values(1,'42');-- ... this will fail

droptable at_tab1, at_tab2;

createtableat_tab1 (aint, btext) partition by list(a);

createtableat_tab2 (xint, y at_tab1);

altertable at_tab1 alter column b typevarchar;-- fails

droptable at_tab1, at_tab2;

createtableat_partitioned (aint, btext) partition by range (a);