in future versions.)

</entry>

</row>

<row>

<entry><literal>parameter_default</literal></entry>

<entry><type>character_data</type></entry>

<entry>

The default expression of the parameter, or null if none or if the

function is not owned by a currently enabled role.

</entry>

</row>

</tbody>

</tgroup>

</table>

CAST(nullAS sql_identifier)AS scope_schema,

CAST(nullAS sql_identifier)AS scope_name,

CAST(nullAS cardinal_number)AS maximum_cardinality,

CAST((ss.x).nAS sql_identifier)AS dtd_identifier

CAST((ss.x).nAS sql_identifier)AS dtd_identifier,

CAST(

CASE WHEN pg_has_role(proowner,'USAGE')

THEN pg_get_function_arg_default(p_oid, (ss.x).n)

ELSENULL END

AS character_data)AS parameter_default

FROM pg_type t, pg_namespace nt,

(SELECTn.nspnameAS n_nspname,p.proname,p.oidAS p_oid,

(SELECTn.nspnameAS n_nspname,p.proname,p.oidAS p_oid,p.proowner,

p.proargnames,p.proargmodes,

_pg_expandarray(coalesce(p.proallargtypes,p.proargtypes::oid[]))AS x

FROM pg_namespace n, pg_proc p

returnargsprinted;

}

is_input_argument(intnth,constchar*argmodes)

{

return (!argmodes

||argmodes[nth]==PROARGMODE_IN

||argmodes[nth]==PROARGMODE_INOUT

||argmodes[nth]==PROARGMODE_VARIADIC);

}

pg_get_function_arg_default(PG_FUNCTION_ARGS)

{

Oidfuncid=PG_GETARG_OID(0);

int32nth_arg=PG_GETARG_INT32(1);

HeapTupleproctup;

Form_pg_procproc;

intnumargs;

Oid*argtypes;

char**argnames;

char*argmodes;

inti;

List*argdefaults;

Node*node;

char*str;

intnth_inputarg;

Datumproargdefaults;

boolisnull;

intnth_default;

proctup=SearchSysCache1(PROCOID,ObjectIdGetDatum(funcid));

if (!HeapTupleIsValid(proctup))

elog(ERROR,"cache lookup failed for function %u",funcid);

numargs=get_func_arg_info(proctup,&argtypes,&argnames,&argmodes);

if (nth_arg<1||nth_arg>numargs|| !is_input_argument(nth_arg-1,argmodes))

{

ReleaseSysCache(proctup);

PG_RETURN_NULL();

}

nth_inputarg=0;

for (i=0;i<nth_arg;i++)

if (is_input_argument(i,argmodes))

nth_inputarg++;

proargdefaults=SysCacheGetAttr(PROCOID,proctup,

Anum_pg_proc_proargdefaults,

&isnull);

if (isnull)

{

ReleaseSysCache(proctup);

PG_RETURN_NULL();

}

str=TextDatumGetCString(proargdefaults);

argdefaults= (List*)stringToNode(str);

Assert(IsA(argdefaults,List));

pfree(str);

proc= (Form_pg_proc)GETSTRUCT(proctup);

nth_default=nth_inputarg-1- (proc->pronargs-proc->pronargdefaults);

if (nth_default<0||nth_default >=list_length(argdefaults))

{

ReleaseSysCache(proctup);

PG_RETURN_NULL();

}

node=list_nth(argdefaults,nth_default);

str=deparse_expression(node,NIL, false, false);

ReleaseSysCache(proctup);

PG_RETURN_TEXT_P(string_to_text(str));

}

DESCR("identity argument list of a function");

DATA(insertOID=2165 (pg_get_function_resultPGNSPPGUID121000fffftfs1025"26"_null__null__null__null_pg_get_function_result_null__null__null_ ));

DESCR("result type of a function");

DATA(insertOID=3808 (pg_get_function_arg_defaultPGNSPPGUID121000fffftfs2025"26 23"_null__null__null__null_pg_get_function_arg_default_null__null__null_ ));

DESCR("function argument default");

DATA(insertOID=1686 (pg_get_keywordsPGNSPPGUID121040000fffftts002249"""{25,18,25}""{o,o,o}""{word,catcode,catdesc}"_null_pg_get_keywords_null__null__null_ ));

DESCR("list of SQL keywords");

externDatumpg_get_function_arguments(PG_FUNCTION_ARGS);

externDatumpg_get_function_identity_arguments(PG_FUNCTION_ARGS);

externDatumpg_get_function_result(PG_FUNCTION_ARGS);

externDatumpg_get_function_arg_default(PG_FUNCTION_ARGS);

externchar*deparse_expression(Node*expr,List*dpcontext,

boolforceprefix,boolshowimplicit);

externList*deparse_context_for(constchar*aliasname,Oidrelid);

functext_f_4 | t

(4 rows)

-- information_schema tests

CREATE FUNCTION functest_IS_1(a int, b int default 1, c text default 'foo')

RETURNS int

LANGUAGE SQL

AS 'SELECT $1 + $2';

CREATE FUNCTION functest_IS_2(out a int, b int default 1)

RETURNS int

LANGUAGE SQL

AS 'SELECT $1';

CREATE FUNCTION functest_IS_3(a int default 1, out b int)

RETURNS int

LANGUAGE SQL

AS 'SELECT $1';

SELECT routine_name, ordinal_position, parameter_name, parameter_default

FROM information_schema.parameters JOIN information_schema.routines USING (specific_schema, specific_name)

WHERE routine_schema = 'temp_func_test' AND routine_name ~ '^functest_is_'

ORDER BY 1, 2;

routine_name | ordinal_position | parameter_name | parameter_default

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

functest_is_1 | 1 | a |

functest_is_1 | 2 | b | 1

functest_is_1 | 3 | c | 'foo'::text

functest_is_2 | 1 | a |

functest_is_2 | 2 | b | 1

functest_is_3 | 1 | a | 1

functest_is_3 | 2 | b |

(7 rows)

-- Cleanups

DROP SCHEMA temp_func_test CASCADE;

NOTICE: drop cascades to16 other objects

NOTICE: drop cascades to19 other objects

DETAIL: drop cascades to function functest_a_1(text,date)

drop cascades to function functest_a_2(text[])

drop cascades to function functest_a_3()

drop cascades to function functext_f_2(integer)

drop cascades to function functext_f_3(integer)

drop cascades to function functext_f_4(integer)

drop cascades to function functest_is_1(integer,integer,text)

drop cascades to function functest_is_2(integer)

drop cascades to function functest_is_3(integer)

DROP USER regtest_unpriv_user;

RESET search_path;

'functext_F_3'::regproc,

'functext_F_4'::regproc)ORDER BY proname;

CREATEFUNCTIONfunctest_IS_1(aint, bint default1, ctext default'foo')

RETURNSint

LANGUAGE SQL

AS'SELECT $1 + $2';

CREATEFUNCTIONfunctest_IS_2(out aint, bint default1)

RETURNSint

LANGUAGE SQL

AS'SELECT $1';

CREATEFUNCTIONfunctest_IS_3(aint default1, out bint)

RETURNSint

LANGUAGE SQL

AS'SELECT $1';

SELECT routine_name, ordinal_position, parameter_name, parameter_default

FROMinformation_schema.parametersJOINinformation_schema.routines USING (specific_schema, specific_name)

WHERE routine_schema='temp_func_test'AND routine_name ~'^functest_is_'

ORDER BY1,2;

DROPSCHEMA temp_func_test CASCADE;

DROPUSER regtest_unpriv_user;