From aefeb68741fb9456f14b4d690b0c646e532fea6b Mon Sep 17 00:00:00 2001 From: Peter Eisentraut Date: Thu, 9 Mar 2017 23:58:48 -0500 Subject: [PATCH] Allow referring to functions without arguments when unique In DDL commands referring to an existing function, allow omitting the argument list if the function name is unique in its schema, per SQL standard. This uses the same logic that the regproc type uses for finding functions by name only. Reviewed-by: Michael Paquier --- doc/src/sgml/ref/alter_extension.sgml | 2 +- doc/src/sgml/ref/alter_function.sgml | 13 ++++--- doc/src/sgml/ref/alter_opfamily.sgml | 7 ++-- doc/src/sgml/ref/comment.sgml | 2 +- doc/src/sgml/ref/create_cast.sgml | 6 ++- doc/src/sgml/ref/create_transform.sgml | 12 ++++-- doc/src/sgml/ref/drop_function.sgml | 35 ++++++++++++++++-- doc/src/sgml/ref/grant.sgml | 2 +- doc/src/sgml/ref/revoke.sgml | 2 +- doc/src/sgml/ref/security_label.sgml | 2 +- src/backend/nodes/copyfuncs.c | 1 + src/backend/nodes/equalfuncs.c | 1 + src/backend/parser/gram.y | 27 ++++++++++++++ src/backend/parser/parse_func.c | 37 +++++++++++++++++-- src/include/nodes/parsenodes.h | 3 ++ .../regress/expected/create_function_3.out | 11 +++++- src/test/regress/sql/create_function_3.sql | 8 ++++ 17 files changed, 143 insertions(+), 28 deletions(-) diff --git a/doc/src/sgml/ref/alter_extension.sgml b/doc/src/sgml/ref/alter_extension.sgml index de6d6dca16..a7c0927d1c 100644 --- a/doc/src/sgml/ref/alter_extension.sgml +++ b/doc/src/sgml/ref/alter_extension.sgml @@ -39,7 +39,7 @@ ALTER EXTENSION name DROP object_name | FOREIGN DATA WRAPPER object_name | FOREIGN TABLE object_name | - FUNCTION function_name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) | + FUNCTION function_name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] | MATERIALIZED VIEW object_name | OPERATOR operator_name (left_type, right_type) | OPERATOR CLASS object_name USING index_method | diff --git a/doc/src/sgml/ref/alter_function.sgml b/doc/src/sgml/ref/alter_function.sgml index 0388d06b95..168eeb7c52 100644 --- a/doc/src/sgml/ref/alter_function.sgml +++ b/doc/src/sgml/ref/alter_function.sgml @@ -21,15 +21,15 @@ PostgreSQL documentation -ALTER FUNCTION name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) +ALTER FUNCTION name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] action [ ... ] [ RESTRICT ] -ALTER FUNCTION name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) +ALTER FUNCTION name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] RENAME TO new_name -ALTER FUNCTION name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) +ALTER FUNCTION name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] OWNER TO { new_owner | CURRENT_USER | SESSION_USER } -ALTER FUNCTION name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) +ALTER FUNCTION name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] SET SCHEMA new_schema -ALTER FUNCTION name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) +ALTER FUNCTION name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] DEPENDS ON EXTENSION extension_name where action is one of: @@ -75,7 +75,8 @@ ALTER FUNCTION name ( [ [ name - The name (optionally schema-qualified) of an existing function. + The name (optionally schema-qualified) of an existing function. If no + argument list is specified, the name must be unique in its schema. diff --git a/doc/src/sgml/ref/alter_opfamily.sgml b/doc/src/sgml/ref/alter_opfamily.sgml index 4511c7f7b2..0bafe5b8f8 100644 --- a/doc/src/sgml/ref/alter_opfamily.sgml +++ b/doc/src/sgml/ref/alter_opfamily.sgml @@ -25,7 +25,7 @@ ALTER OPERATOR FAMILY name USING strategy_number operator_name ( op_type, op_type ) [ FOR SEARCH | FOR ORDER BY sort_family_name ] | FUNCTION support_number [ ( op_type [ , op_type ] ) ] - function_name ( argument_type [, ...] ) + function_name [ ( argument_type [, ...] ) ] } [, ... ] ALTER OPERATOR FAMILY name USING index_method DROP @@ -195,8 +195,9 @@ ALTER OPERATOR FAMILY name USING function_name - The name (optionally schema-qualified) of a function that is an - index method support procedure for the operator family. + The name (optionally schema-qualified) of a function that is an index + method support procedure for the operator family. If no argument list + is specified, the name must be unique in its schema. diff --git a/doc/src/sgml/ref/comment.sgml b/doc/src/sgml/ref/comment.sgml index c1cf587cb2..7483c8c03f 100644 --- a/doc/src/sgml/ref/comment.sgml +++ b/doc/src/sgml/ref/comment.sgml @@ -37,7 +37,7 @@ COMMENT ON EVENT TRIGGER object_name | FOREIGN DATA WRAPPER object_name | FOREIGN TABLE object_name | - FUNCTION function_name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) | + FUNCTION function_name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] | INDEX object_name | LARGE OBJECT large_object_oid | MATERIALIZED VIEW object_name | diff --git a/doc/src/sgml/ref/create_cast.sgml b/doc/src/sgml/ref/create_cast.sgml index 11266755e5..a7d13edc22 100644 --- a/doc/src/sgml/ref/create_cast.sgml +++ b/doc/src/sgml/ref/create_cast.sgml @@ -19,7 +19,7 @@ CREATE CAST (source_type AS target_type) - WITH FUNCTION function_name (argument_type [, ...]) + WITH FUNCTION function_name [ (argument_type [, ...]) ] [ AS ASSIGNMENT | AS IMPLICIT ] CREATE CAST (source_type AS target_type) @@ -192,7 +192,7 @@ SELECT CAST ( 2 AS numeric ) + 4.0; - function_name(argument_type [, ...]) + function_name[(argument_type [, ...])] @@ -200,6 +200,8 @@ SELECT CAST ( 2 AS numeric ) + 4.0; be schema-qualified. If it is not, the function will be looked up in the schema search path. The function's result data type must match the target type of the cast. Its arguments are discussed below. + If no argument list is specified, the function name must be unique in + its schema. diff --git a/doc/src/sgml/ref/create_transform.sgml b/doc/src/sgml/ref/create_transform.sgml index f44ee89d33..647c3b9f05 100644 --- a/doc/src/sgml/ref/create_transform.sgml +++ b/doc/src/sgml/ref/create_transform.sgml @@ -19,8 +19,8 @@ CREATE [ OR REPLACE ] TRANSFORM FOR type_name LANGUAGE lang_name ( - FROM SQL WITH FUNCTION from_sql_function_name (argument_type [, ...]), - TO SQL WITH FUNCTION to_sql_function_name (argument_type [, ...]) + FROM SQL WITH FUNCTION from_sql_function_name [ (argument_type [, ...]) ], + TO SQL WITH FUNCTION to_sql_function_name [ (argument_type [, ...]) ] ); @@ -104,7 +104,7 @@ CREATE [ OR REPLACE ] TRANSFORM FOR type_name LANGUAG - from_sql_function_name(argument_type [, ...]) + from_sql_function_name[(argument_type [, ...])] @@ -116,12 +116,14 @@ CREATE [ OR REPLACE ] TRANSFORM FOR type_name LANGUAG SQL-level function returning internal without at least one argument of type internal.) The actual return value will be something specific to the language implementation. + If no argument list is specified, the function name must be unique in + its schema. - to_sql_function_name(argument_type [, ...]) + to_sql_function_name[(argument_type [, ...])] @@ -130,6 +132,8 @@ CREATE [ OR REPLACE ] TRANSFORM FOR type_name LANGUAG internal and return the type that is the type for the transform. The actual argument value will be something specific to the language implementation. + If no argument list is specified, the function name must be unique in + its schema. diff --git a/doc/src/sgml/ref/drop_function.sgml b/doc/src/sgml/ref/drop_function.sgml index 5969b084b4..0aa984528d 100644 --- a/doc/src/sgml/ref/drop_function.sgml +++ b/doc/src/sgml/ref/drop_function.sgml @@ -21,7 +21,7 @@ PostgreSQL documentation -DROP FUNCTION [ IF EXISTS ] name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) [, ...] +DROP FUNCTION [ IF EXISTS ] name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] [, ...] [ CASCADE | RESTRICT ] @@ -56,7 +56,8 @@ DROP FUNCTION [ IF EXISTS ] name ( name - The name (optionally schema-qualified) of an existing function. + The name (optionally schema-qualified) of an existing function. If no + argument list is specified, the name must be unique in its schema. @@ -141,14 +142,40 @@ DROP FUNCTION sqrt(integer); DROP FUNCTION sqrt(integer), sqrt(bigint); + + + If the function name is unique in its schema, it can be referred to without + an argument list: + +DROP FUNCTION update_employee_salaries; + + Note that this is different from + +DROP FUNCTION update_employee_salaries(); + + which refers to a function with zero arguments, whereas the first variant + can refer to a function with any number of arguments, including zero, as + long as the name is unique. + Compatibility - A DROP FUNCTION statement is defined in the SQL - standard, but it is not compatible with this command. + This command conforms to the SQL standard, with + these PostgreSQL extensions: + + + The standard only allows one function to be dropped per command. + + + The IF EXISTS option + + + The ability to specify argument modes and names + + diff --git a/doc/src/sgml/ref/grant.sgml b/doc/src/sgml/ref/grant.sgml index d8ca39f869..9fb4c2fd7e 100644 --- a/doc/src/sgml/ref/grant.sgml +++ b/doc/src/sgml/ref/grant.sgml @@ -55,7 +55,7 @@ GRANT { USAGE | ALL [ PRIVILEGES ] } TO role_specification [, ...] [ WITH GRANT OPTION ] GRANT { EXECUTE | ALL [ PRIVILEGES ] } - ON { FUNCTION function_name ( [ [ argmode ] [ arg_name ] arg_type [, ...] ] ) [, ...] + ON { FUNCTION function_name [ ( [ [ argmode ] [ arg_name ] arg_type [, ...] ] ) ] [, ...] | ALL FUNCTIONS IN SCHEMA schema_name [, ...] } TO role_specification [, ...] [ WITH GRANT OPTION ] diff --git a/doc/src/sgml/ref/revoke.sgml b/doc/src/sgml/ref/revoke.sgml index fc00129620..ce532543f0 100644 --- a/doc/src/sgml/ref/revoke.sgml +++ b/doc/src/sgml/ref/revoke.sgml @@ -70,7 +70,7 @@ REVOKE [ GRANT OPTION FOR ] REVOKE [ GRANT OPTION FOR ] { EXECUTE | ALL [ PRIVILEGES ] } - ON { FUNCTION function_name ( [ [ argmode ] [ arg_name ] arg_type [, ...] ] ) [, ...] + ON { FUNCTION function_name [ ( [ [ argmode ] [ arg_name ] arg_type [, ...] ] ) ] [, ...] | ALL FUNCTIONS IN SCHEMA schema_name [, ...] } FROM { [ GROUP ] role_name | PUBLIC } [, ...] [ CASCADE | RESTRICT ] diff --git a/doc/src/sgml/ref/security_label.sgml b/doc/src/sgml/ref/security_label.sgml index 998fe3b7c0..afd86aff3a 100644 --- a/doc/src/sgml/ref/security_label.sgml +++ b/doc/src/sgml/ref/security_label.sgml @@ -30,7 +30,7 @@ SECURITY LABEL [ FOR provider ] ON DOMAIN object_name | EVENT TRIGGER object_name | FOREIGN TABLE object_name - FUNCTION function_name ( [ [ argmode ] [ argname ] argtype [, ...] ] ) | + FUNCTION function_name [ ( [ [ argmode ] [ argname ] argtype [, ...] ] ) ] | LARGE OBJECT large_object_oid | MATERIALIZED VIEW object_name | [ PROCEDURAL ] LANGUAGE object_name | diff --git a/src/backend/nodes/copyfuncs.c b/src/backend/nodes/copyfuncs.c index bfc2ac1716..25fd051d6e 100644 --- a/src/backend/nodes/copyfuncs.c +++ b/src/backend/nodes/copyfuncs.c @@ -3067,6 +3067,7 @@ _copyObjectWithArgs(const ObjectWithArgs *from) COPY_NODE_FIELD(objname); COPY_NODE_FIELD(objargs); + COPY_SCALAR_FIELD(args_unspecified); return newnode; } diff --git a/src/backend/nodes/equalfuncs.c b/src/backend/nodes/equalfuncs.c index 54e9c983a0..67529e3f86 100644 --- a/src/backend/nodes/equalfuncs.c +++ b/src/backend/nodes/equalfuncs.c @@ -1119,6 +1119,7 @@ _equalObjectWithArgs(const ObjectWithArgs *a, const ObjectWithArgs *b) { COMPARE_NODE_FIELD(objname); COMPARE_NODE_FIELD(objargs); + COMPARE_SCALAR_FIELD(args_unspecified); return true; } diff --git a/src/backend/parser/gram.y b/src/backend/parser/gram.y index e7acc2d9a2..6316688a88 100644 --- a/src/backend/parser/gram.y +++ b/src/backend/parser/gram.y @@ -7202,6 +7202,33 @@ function_with_argtypes: n->objargs = extractArgTypes($2); $$ = n; } + /* + * Because of reduce/reduce conflicts, we can't use func_name + * below, but we can write it out the long way, which actually + * allows more cases. + */ + | type_func_name_keyword + { + ObjectWithArgs *n = makeNode(ObjectWithArgs); + n->objname = list_make1(makeString(pstrdup($1))); + n->args_unspecified = true; + $$ = n; + } + | ColId + { + ObjectWithArgs *n = makeNode(ObjectWithArgs); + n->objname = list_make1(makeString($1)); + n->args_unspecified = true; + $$ = n; + } + | ColId indirection + { + ObjectWithArgs *n = makeNode(ObjectWithArgs); + n->objname = check_func_name(lcons(makeString($1), $2), + yyscanner); + n->args_unspecified = true; + $$ = n; + } ; /* diff --git a/src/backend/parser/parse_func.c b/src/backend/parser/parse_func.c index dd9749f205..55853c20bb 100644 --- a/src/backend/parser/parse_func.c +++ b/src/backend/parser/parse_func.c @@ -1895,8 +1895,10 @@ func_signature_string(List *funcname, int nargs, /* * LookupFuncName - * Given a possibly-qualified function name and a set of argument types, - * look up the function. + * + * Given a possibly-qualified function name and optionally a set of argument + * types, look up the function. Pass nargs == -1 to indicate that no argument + * types are specified. * * If the function name is not schema-qualified, it is sought in the current * namespace search path. @@ -1914,6 +1916,35 @@ LookupFuncName(List *funcname, int nargs, const Oid *argtypes, bool noError) clist = FuncnameGetCandidates(funcname, nargs, NIL, false, false, noError); + /* + * If no arguments were specified, the name must yield a unique candidate. + */ + if (nargs == -1) + { + if (clist) + { + if (clist->next) + { + if (!noError) + ereport(ERROR, + (errcode(ERRCODE_AMBIGUOUS_FUNCTION), + errmsg("function name \"%s\" is not unique", + NameListToString(funcname)), + errhint("Specify the argument list to select the function unambiguously."))); + } + else + return clist->oid; + } + else + { + if (!noError) + ereport(ERROR, + (errcode(ERRCODE_UNDEFINED_FUNCTION), + errmsg("could not find a function named \"%s\"", + NameListToString(funcname)))); + } + } + while (clist) { if (memcmp(argtypes, clist->args, nargs * sizeof(Oid)) == 0) @@ -1962,7 +1993,7 @@ LookupFuncWithArgs(ObjectWithArgs *func, bool noError) args_item = lnext(args_item); } - return LookupFuncName(func->objname, argcount, argoids, noError); + return LookupFuncName(func->objname, func->args_unspecified ? -1 : argcount, argoids, noError); } /* diff --git a/src/include/nodes/parsenodes.h b/src/include/nodes/parsenodes.h index a44d2178e1..d576523f6a 100644 --- a/src/include/nodes/parsenodes.h +++ b/src/include/nodes/parsenodes.h @@ -1811,6 +1811,9 @@ typedef struct ObjectWithArgs NodeTag type; List *objname; /* qualified name of function/operator */ List *objargs; /* list of Typename nodes */ + bool args_unspecified; /* argument list was omitted, so name must + * be unique (note that objargs == NIL means + * zero args) */ } ObjectWithArgs; /* diff --git a/src/test/regress/expected/create_function_3.out b/src/test/regress/expected/create_function_3.out index cc4e98a1d4..b5e19485e5 100644 --- a/src/test/regress/expected/create_function_3.out +++ b/src/test/regress/expected/create_function_3.out @@ -218,13 +218,21 @@ SELECT routine_name, ordinal_position, parameter_name, parameter_default (7 rows) DROP FUNCTION functest_IS_1(int, int, text), functest_IS_2(int), functest_IS_3(int); +-- overload +CREATE FUNCTION functest_B_2(bigint) RETURNS bool LANGUAGE 'sql' + IMMUTABLE AS 'SELECT $1 > 0'; +DROP FUNCTION functest_b_1; +DROP FUNCTION functest_b_1; -- error, not found +ERROR: could not find a function named "functest_b_1" +DROP FUNCTION functest_b_2; -- error, ambiguous +ERROR: function name "functest_b_2" is not unique +HINT: Specify the argument list to select the function unambiguously. -- Cleanups DROP SCHEMA temp_func_test CASCADE; NOTICE: drop cascades to 16 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 functest_b_1(integer) drop cascades to function functest_b_2(integer) drop cascades to function functest_b_3(integer) drop cascades to function functest_b_4(integer) @@ -237,5 +245,6 @@ drop cascades to function functext_f_1(integer) 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_b_2(bigint) DROP USER regress_unpriv_user; RESET search_path; diff --git a/src/test/regress/sql/create_function_3.sql b/src/test/regress/sql/create_function_3.sql index 66a463b089..0a0e407aab 100644 --- a/src/test/regress/sql/create_function_3.sql +++ b/src/test/regress/sql/create_function_3.sql @@ -158,6 +158,14 @@ SELECT routine_name, ordinal_position, parameter_name, parameter_default DROP FUNCTION functest_IS_1(int, int, text), functest_IS_2(int), functest_IS_3(int); +-- overload +CREATE FUNCTION functest_B_2(bigint) RETURNS bool LANGUAGE 'sql' + IMMUTABLE AS 'SELECT $1 > 0'; + +DROP FUNCTION functest_b_1; +DROP FUNCTION functest_b_1; -- error, not found +DROP FUNCTION functest_b_2; -- error, ambiguous + -- Cleanups DROP SCHEMA temp_func_test CASCADE; -- 2.40.0