<entry><structfield>conbin</structfield></entry>

<entry><type>pg_node_tree</type></entry>

<entry></entry>

<entry>If a check constraint, an internal representation of the expression</entry>

</row>

<row>

<entry><structfield>consrc</structfield></entry>

<entry><type>text</type></entry>

<entry></entry>

<entry>If a check constraint, a human-readable representation of the expression</entry>

<entry>If a check constraint, an internal representation of the

expression. (It's recommended to use

<function>pg_get_constraintdef()</function> to extract the definition of

a check constraint.)</entry>

</row>

</tbody>

</tgroup>

index.)

</para>

<note>

<para>

<structfield>consrc</structfield> is not updated when referenced objects

change; for example, it won't track renaming of columns. Rather than

relying on this field, it's best to use <function>pg_get_constraintdef()</function>

to extract the definition of a check constraint.

</para>

</note>

<note>

<para>

<literal>pg_class.relchecks</literal> needs to agree with the

boolis_no_inherit,boolis_internal)

{

char*ccbin;

char*ccsrc;

List*varList;

intkeycount;

int16*attNos;

ccbin=nodeToString(expr);

ccsrc=deparse_expression(expr,

deparse_context_for(RelationGetRelationName(rel),

RelationGetRelid(rel)),

false, false);

NULL,/* not an exclusion constraint */

expr,/* Tree form of check constraint */

ccbin,/* Binary form of check constraint */

ccsrc,/* Source form of check constraint */

is_local,/* conislocal */

inhcount,/* coninhcount */

is_no_inherit,/* connoinherit */

is_internal);/* internally constructed? */

pfree(ccbin);

pfree(ccsrc);

returnconstrOid;

}

indexInfo->ii_ExclusionOps,

NULL,/* no check constraint */

NULL,

NULL,

islocal,

inhcount,

noinherit,

constOid*exclOp,

Node*conExpr,

constchar*conBin,

constchar*conSrc,

boolconIsLocal,

intconInhCount,

boolconNoInherit,

nulls[Anum_pg_constraint_conexclop-1]= true;

if (conBin)

values[Anum_pg_constraint_conbin-1]=CStringGetTextDatum(conBin);

nulls[Anum_pg_constraint_conbin-1]= true;

if (conSrc)

values[Anum_pg_constraint_consrc-1]=CStringGetTextDatum(conSrc);

nulls[Anum_pg_constraint_consrc-1]= true;

tup=heap_form_tuple(RelationGetDescr(conDesc),values,nulls);

conOid=CatalogTupleInsert(conDesc,tup);

NULL,

NULL,

NULL,

NULL,

false,

1, false, true);

subclone=lappend_oid(subclone,constrOid);

NULL,/* no exclusion constraint */

NULL,/* no check constraint */

NULL,

NULL,

true,/* islocal */

0,/* inhcount */

true,/* isnoinherit */

NULL,/* no exclusion */

NULL,/* no check constraint */

NULL,

NULL,

true,/* islocal */

0,/* inhcount */

true,/* isnoinherit */

constchar*domainName,ObjectAddress*constrAddr)

{

Node*expr;

char*ccsrc;

char*ccbin;

ParseState*pstate;

CoerceToDomainValue*domVal;

ccbin=nodeToString(expr);

ccsrc=deparse_expression(expr,

NIL, false, false);

NULL,/* not an exclusion constraint */

expr,/* Tree form of check constraint */

ccbin,/* Binary form of check constraint */

ccsrc,/* Source form of check constraint */

true,/* is local */

0,/* inhcount */

false,/* connoinherit */

pg_node_treeconbin;

textconsrc;

}FormData_pg_constraint;

constOid*exclOp,

Node*conExpr,

constchar*conBin,

constchar*conSrc,

boolconIsLocal,

intconInhCount,

boolconNoInherit,

CREATE TABLE ac (aa TEXT);

alter table ac add constraint ac_check check (aa is not null);

CREATE TABLE bc (bb TEXT) INHERITS (ac);

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+----------+---------+------------+-------------+------------------

ac | ac_check | c | t | 0 | (aa IS NOT NULL)

alter table bc drop constraint ac_check; -- fail, disallowed

ERROR: cannot drop inherited constraint "ac_check" of relation "bc"

alter table ac drop constraint ac_check;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+--------

(0 rows)

-- try the unnamed-constraint case

alter table ac add check (aa is not null);

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+-------------+---------+------------+-------------+------------------

ac | ac_aa_check | c | t | 0 | (aa IS NOT NULL)

alter table bc drop constraint ac_aa_check; -- fail, disallowed

ERROR: cannot drop inherited constraint "ac_aa_check" of relation "bc"

alter table ac drop constraint ac_aa_check;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+--------

(0 rows)

alter table ac add constraint ac_check check (aa is not null);

alter table bc no inherit ac;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+----------+---------+------------+-------------+------------------

ac | ac_check | c | t | 0 | (aa IS NOT NULL)

bc | ac_check | c | t | 0 | (aa IS NOT NULL)

(2 rows)

alter table bc drop constraint ac_check;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+----------+---------+------------+-------------+------------------

ac | ac_check | c | t | 0 | (aa IS NOT NULL)

(1 row)

alter table ac drop constraint ac_check;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+--------

(0 rows)

create table bc (a int constraint check_a check (a <> 0), b int constraint check_b check (b <> 0)) inherits (ac);

NOTICE: merging column "a" with inherited definition

NOTICE: merging constraint "check_a" with inherited definition

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+----------

ac | check_a | c | t | 0 | (a <> 0)

create table ac (a int constraint check_a check (a <> 0));

create table bc (b int constraint check_b check (b <> 0));

create table cc (c int constraint check_c check (c <> 0)) inherits (ac, bc);

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+----------

ac | check_a | c | t | 0 | (a <> 0)

(5 rows)

alter table cc no inherit bc;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount, pgc.consrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;

select pc.relname, pgc.conname, pgc.contype, pgc.conislocal, pgc.coninhcount,pg_get_expr(pgc.conbin, pc.oid) asconsrc from pg_class as pc inner join pg_constraint as pgc on (pgc.conrelid = pc.oid) where pc.relname in ('ac', 'bc', 'cc') order by 1,2;

relname | conname | contype | conislocal | coninhcount | consrc

---------+---------+---------+------------+-------------+----------

ac | check_a | c | t | 0 | (a <> 0)