diff --git a/contrib/postgres_fdw/deparse.c b/contrib/postgres_fdw/deparse.c index d98bd66681..67d397c354 100644 --- a/contrib/postgres_fdw/deparse.c +++ b/contrib/postgres_fdw/deparse.c @@ -2695,9 +2695,12 @@ deparseVar(Var *node, deparse_expr_cxt *context) * Deparse given constant value into context->buf. * * This function has to be kept in sync with ruleutils.c's get_const_expr. - * As for that function, showtype can be -1 to never show "::typename" decoration, - * or +1 to always show it, or 0 to show it only if the constant wouldn't be assumed - * to be the right type by default. + * As in that function, showtype can be -1 to never show "::typename" + * decoration, or +1 to always show it, or 0 to show it only if the constant + * wouldn't be assumed to be the right type by default. In addition, + * this code allows showtype to be -2 to indicate that we should not show + * "::typename" decoration if the constant is printed as an untyped literal + * or NULL (while in other cases, behaving as for showtype == 0). */ static void deparseConst(Const *node, deparse_expr_cxt *context, int showtype) @@ -2707,6 +2710,7 @@ deparseConst(Const *node, deparse_expr_cxt *context, int showtype) bool typIsVarlena; char *extval; bool isfloat = false; + bool isstring = false; bool needlabel; if (node->constisnull) @@ -2762,13 +2766,14 @@ deparseConst(Const *node, deparse_expr_cxt *context, int showtype) break; default: deparseStringLiteral(buf, extval); + isstring = true; break; } pfree(extval); - if (showtype < 0) - return; + if (showtype == -1) + return; /* never print type label */ /* * For showtype == 0, append ::typename unless the constant will be @@ -2788,7 +2793,13 @@ deparseConst(Const *node, deparse_expr_cxt *context, int showtype) needlabel = !isfloat || (node->consttypmod >= 0); break; default: - needlabel = true; + if (showtype == -2) + { + /* label unless we printed it as an untyped string */ + needlabel = !isstring; + } + else + needlabel = true; break; } if (needlabel || showtype > 0) @@ -2953,6 +2964,8 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context) StringInfo buf = context->buf; HeapTuple tuple; Form_pg_operator form; + Expr *right; + bool treatRightConstSpecially = false; char oprkind; /* Retrieve information about the operator from system catalog. */ @@ -2966,13 +2979,51 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context) Assert((oprkind == 'l' && list_length(node->args) == 1) || (oprkind == 'b' && list_length(node->args) == 2)); + right = llast(node->args); + /* Always parenthesize the expression. */ appendStringInfoChar(buf, '('); /* Deparse left operand, if any. */ if (oprkind == 'b') { - deparseExpr(linitial(node->args), context); + Expr *left = linitial(node->args); + Oid leftType = exprType((Node *) left); + Oid rightType = exprType((Node *) right); + bool treatLeftConstSpecially = false; + + /* + * When considering a binary operator, if one input is a Const that + * can be printed as a bare string literal or NULL (i.e., it will look + * like type UNKNOWN to the remote parser), while the other input + * isn't a Const, we prefer to suppress the explicit cast that would + * normally get attached to the Const. We can do so if its type is + * the same as the other input's type. This relies on the remote + * parser applying the heuristic that says to resolve ambiguous + * operator calls with one unknown and one known input type by + * assuming that the unknown input is of the same type as the known + * input. + * + * Doing things this way allows some cases to succeed where a remote + * table's column is not of the identical type it was declared as in + * the local foreign table. By emitting, say, "foreigncol = 'foo'" + * not "foreigncol = 'foo'::text", we allow the remote parser to pick + * an "=" operator that's compatible with whatever the column really + * is remotely. + */ + if (leftType == rightType) + { + if (IsA(left, Const) && !IsA(right, Const)) + treatLeftConstSpecially = true; + else if (IsA(right, Const) && !IsA(left, Const)) + treatRightConstSpecially = true; + } + + if (treatLeftConstSpecially) + deparseConst((Const *) left, context, -2); + else + deparseExpr(left, context); + appendStringInfoChar(buf, ' '); } @@ -2981,7 +3032,11 @@ deparseOpExpr(OpExpr *node, deparse_expr_cxt *context) /* Deparse right operand. */ appendStringInfoChar(buf, ' '); - deparseExpr(llast(node->args), context); + + if (treatRightConstSpecially) + deparseConst((Const *) right, context, -2); + else + deparseExpr(right, context); appendStringInfoChar(buf, ')'); diff --git a/contrib/postgres_fdw/expected/postgres_fdw.out b/contrib/postgres_fdw/expected/postgres_fdw.out index fd141a0fa5..8b4305ef88 100644 --- a/contrib/postgres_fdw/expected/postgres_fdw.out +++ b/contrib/postgres_fdw/expected/postgres_fdw.out @@ -341,11 +341,11 @@ SELECT * FROM ft1 WHERE false; -- with WHERE clause EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE t1.c1 = 101 AND t1.c6 = '1' AND t1.c7 >= '1'; - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------- + QUERY PLAN +---------------------------------------------------------------------------------------------------------------------------------- Foreign Scan on public.ft1 t1 Output: c1, c2, c3, c4, c5, c6, c7, c8 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c7 >= '1'::bpchar)) AND (("C 1" = 101)) AND ((c6 = '1'::text)) + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c7 >= '1')) AND (("C 1" = 101)) AND ((c6 = '1')) (3 rows) SELECT * FROM ft1 t1 WHERE t1.c1 = 101 AND t1.c6 = '1' AND t1.c7 >= '1'; @@ -707,11 +707,11 @@ EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c1 = (ARRAY[c1,c2,3])[1] (3 rows) EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c6 = E'foo''s\\bar'; -- check special chars - QUERY PLAN -------------------------------------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------------------------------------- Foreign Scan on public.ft1 t1 Output: c1, c2, c3, c4, c5, c6, c7, c8 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c6 = E'foo''s\\bar'::text)) + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c6 = E'foo''s\\bar')) (3 rows) EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE c8 = 'foo'; -- can't be sent to remote @@ -1130,20 +1130,20 @@ SELECT * FROM ft1 WHERE c1 > (CASE random()::integer WHEN 0 THEN 1 WHEN 2 THEN 5 -- these are shippable EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 WHERE CASE c6 WHEN 'foo' THEN true ELSE c3 < 'bar' END; - QUERY PLAN --------------------------------------------------------------------------------------------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------------------------------------------------------------------------------- Foreign Scan on public.ft1 Output: c1, c2, c3, c4, c5, c6, c7, c8 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((CASE c6 WHEN 'foo'::text THEN true ELSE (c3 < 'bar'::text) END)) + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((CASE c6 WHEN 'foo'::text THEN true ELSE (c3 < 'bar') END)) (3 rows) EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 WHERE CASE c3 WHEN c6 THEN true ELSE c3 < 'bar' END; - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------------------------------------------------------------------------- Foreign Scan on public.ft1 Output: c1, c2, c3, c4, c5, c6, c7, c8 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((CASE c3 WHEN c6 THEN true ELSE (c3 < 'bar'::text) END)) + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((CASE c3 WHEN c6 THEN true ELSE (c3 < 'bar') END)) (3 rows) -- but this is not because of collation @@ -3491,12 +3491,12 @@ ORDER BY ref_0."C 1"; Index Cond: (ref_0."C 1" < 10) -> Foreign Scan on public.ft1 ref_1 Output: ref_1.c3, ref_0.c2 - Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE ((c3 = '00001'::text)) + Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE ((c3 = '00001')) -> Materialize Output: ref_3.c3 -> Foreign Scan on public.ft2 ref_3 Output: ref_3.c3 - Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE ((c3 = '00001'::text)) + Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE ((c3 = '00001')) (15 rows) SELECT ref_0.c2, subq_1.* @@ -3841,8 +3841,8 @@ EXECUTE st2(101, 121); -- subquery using immutable function (can be sent to remote) PREPARE st3(int) AS SELECT * FROM ft1 t1 WHERE t1.c1 < $2 AND t1.c3 IN (SELECT c3 FROM ft2 t2 WHERE c1 > $1 AND date(c5) = '1970-01-17'::date) ORDER BY c1; EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st3(10, 20); - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------------------------------------------------------- Sort Output: t1.c1, t1.c2, t1.c3, t1.c4, t1.c5, t1.c6, t1.c7, t1.c8 Sort Key: t1.c1 @@ -3856,7 +3856,7 @@ EXPLAIN (VERBOSE, COSTS OFF) EXECUTE st3(10, 20); Output: t2.c3 -> Foreign Scan on public.ft2 t2 Output: t2.c3 - Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE (("C 1" > 10)) AND ((date(c5) = '1970-01-17'::date)) + Remote SQL: SELECT c3 FROM "S 1"."T 1" WHERE (("C 1" > 10)) AND ((date(c5) = '1970-01-17')) (14 rows) EXECUTE st3(10, 20); @@ -4114,11 +4114,11 @@ SELECT tableoid::regclass, * FROM ft1 t1 LIMIT 1; EXPLAIN (VERBOSE, COSTS OFF) SELECT * FROM ft1 t1 WHERE t1.ctid = '(0,2)'; - QUERY PLAN -------------------------------------------------------------------------------------------------------- + QUERY PLAN +-------------------------------------------------------------------------------------------------- Foreign Scan on public.ft1 t1 Output: c1, c2, c3, c4, c5, c6, c7, c8 - Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((ctid = '(0,2)'::tid)) + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((ctid = '(0,2)')) (3 rows) SELECT * FROM ft1 t1 WHERE t1.ctid = '(0,2)'; @@ -4205,6 +4205,53 @@ ERROR: invalid input syntax for type integer: "foo" CONTEXT: column "c8" of foreign table "ft1" ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE user_enum; -- =================================================================== +-- local type can be different from remote type in some cases, +-- in particular if similarly-named operators do equivalent things +-- =================================================================== +ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE text; +EXPLAIN (VERBOSE, COSTS OFF) +SELECT * FROM ft1 WHERE c8 = 'foo' LIMIT 1; + QUERY PLAN +-------------------------------------------------------------------------------------------------------------- + Foreign Scan on public.ft1 + Output: c1, c2, c3, c4, c5, c6, c7, c8 + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c8 = 'foo')) LIMIT 1::bigint +(3 rows) + +SELECT * FROM ft1 WHERE c8 = 'foo' LIMIT 1; + c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 +----+----+-------+------------------------------+--------------------------+----+------------+----- + 1 | 1 | 00001 | Fri Jan 02 00:00:00 1970 PST | Fri Jan 02 00:00:00 1970 | 1 | 1 | foo +(1 row) + +EXPLAIN (VERBOSE, COSTS OFF) +SELECT * FROM ft1 WHERE 'foo' = c8 LIMIT 1; + QUERY PLAN +-------------------------------------------------------------------------------------------------------------- + Foreign Scan on public.ft1 + Output: c1, c2, c3, c4, c5, c6, c7, c8 + Remote SQL: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE (('foo' = c8)) LIMIT 1::bigint +(3 rows) + +SELECT * FROM ft1 WHERE 'foo' = c8 LIMIT 1; + c1 | c2 | c3 | c4 | c5 | c6 | c7 | c8 +----+----+-------+------------------------------+--------------------------+----+------------+----- + 1 | 1 | 00001 | Fri Jan 02 00:00:00 1970 PST | Fri Jan 02 00:00:00 1970 | 1 | 1 | foo +(1 row) + +-- we declared c8 to be text locally, but it's still the same type on +-- the remote which will balk if we try to do anything incompatible +-- with that remote type +SELECT * FROM ft1 WHERE c8 LIKE 'foo' LIMIT 1; -- ERROR +ERROR: operator does not exist: public.user_enum ~~ unknown +HINT: No operator matches the given name and argument types. You might need to add explicit type casts. +CONTEXT: remote SQL command: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c8 ~~ 'foo')) LIMIT 1::bigint +SELECT * FROM ft1 WHERE c8::text LIKE 'foo' LIMIT 1; -- ERROR +ERROR: operator does not exist: public.user_enum ~~ unknown +HINT: No operator matches the given name and argument types. You might need to add explicit type casts. +CONTEXT: remote SQL command: SELECT "C 1", c2, c3, c4, c5, c6, c7, c8 FROM "S 1"."T 1" WHERE ((c8 ~~ 'foo')) LIMIT 1::bigint +ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE user_enum; +-- =================================================================== -- subtransaction -- + local/remote error doesn't break cursor -- =================================================================== @@ -4254,35 +4301,35 @@ create foreign table ft3 (f1 text collate "C", f2 text, f3 varchar(10)) server loopback options (table_name 'loct3', use_remote_estimate 'true'); -- can be sent to remote explain (verbose, costs off) select * from ft3 where f1 = 'foo'; - QUERY PLAN ------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------ Foreign Scan on public.ft3 Output: f1, f2, f3 - Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f1 = 'foo'::text)) + Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f1 = 'foo')) (3 rows) explain (verbose, costs off) select * from ft3 where f1 COLLATE "C" = 'foo'; - QUERY PLAN ------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------ Foreign Scan on public.ft3 Output: f1, f2, f3 - Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f1 = 'foo'::text)) + Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f1 = 'foo')) (3 rows) explain (verbose, costs off) select * from ft3 where f2 = 'foo'; - QUERY PLAN ------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------ Foreign Scan on public.ft3 Output: f1, f2, f3 - Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f2 = 'foo'::text)) + Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f2 = 'foo')) (3 rows) explain (verbose, costs off) select * from ft3 where f3 = 'foo'; - QUERY PLAN ------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------ Foreign Scan on public.ft3 Output: f1, f2, f3 - Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f3 = 'foo'::text)) + Remote SQL: SELECT f1, f2, f3 FROM public.loct3 WHERE ((f3 = 'foo')) (3 rows) explain (verbose, costs off) select * from ft3 f, loct3 l @@ -4384,22 +4431,22 @@ INSERT INTO ft2 (c1,c2,c3) INSERT INTO ft2 (c1,c2,c3) VALUES (1104,204,'ddd'), (1105,205,'eee'); EXPLAIN (verbose, costs off) UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3; -- can be pushed down - QUERY PLAN ----------------------------------------------------------------------------------------------------------------------- + QUERY PLAN +---------------------------------------------------------------------------------------------------------------- Update on public.ft2 -> Foreign Update on public.ft2 - Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 300), c3 = (c3 || '_update3'::text) WHERE ((("C 1" % 10) = 3)) + Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 300), c3 = (c3 || '_update3') WHERE ((("C 1" % 10) = 3)) (3 rows) UPDATE ft2 SET c2 = c2 + 300, c3 = c3 || '_update3' WHERE c1 % 10 = 3; EXPLAIN (verbose, costs off) UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *; -- can be pushed down - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------- + QUERY PLAN +------------------------------------------------------------------------------------------------------------------------------------------------------------ Update on public.ft2 Output: c1, c2, c3, c4, c5, c6, c7, c8 -> Foreign Update on public.ft2 - Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 400), c3 = (c3 || '_update7'::text) WHERE ((("C 1" % 10) = 7)) RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8 + Remote SQL: UPDATE "S 1"."T 1" SET c2 = (c2 + 400), c3 = (c3 || '_update7') WHERE ((("C 1" % 10) = 7)) RETURNING "C 1", c2, c3, c4, c5, c6, c7, c8 (4 rows) UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING *; @@ -4512,11 +4559,11 @@ UPDATE ft2 SET c2 = c2 + 400, c3 = c3 || '_update7' WHERE c1 % 10 = 7 RETURNING EXPLAIN (verbose, costs off) UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT FROM ft1 WHERE ft1.c1 = ft2.c2 AND ft1.c1 % 10 = 9; -- can be pushed down - QUERY PLAN ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------ + QUERY PLAN +----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- Update on public.ft2 -> Foreign Update - Remote SQL: UPDATE "S 1"."T 1" r1 SET c2 = (r1.c2 + 500), c3 = (r1.c3 || '_update9'::text), c7 = 'ft2 '::character(10) FROM "S 1"."T 1" r2 WHERE ((r1.c2 = r2."C 1")) AND (((r2."C 1" % 10) = 9)) + Remote SQL: UPDATE "S 1"."T 1" r1 SET c2 = (r1.c2 + 500), c3 = (r1.c3 || '_update9'), c7 = 'ft2 '::character(10) FROM "S 1"."T 1" r2 WHERE ((r1.c2 = r2."C 1")) AND (((r2."C 1" % 10) = 9)) (3 rows) UPDATE ft2 SET c2 = ft2.c2 + 500, c3 = ft2.c3 || '_update9', c7 = DEFAULT @@ -8129,7 +8176,7 @@ select tableoid::regclass, * FROM locp; update utrtest set a = 2 where b = 'foo' returning *; ERROR: new row for relation "loct" violates check constraint "loct_a_check" DETAIL: Failing row contains (2, foo). -CONTEXT: remote SQL command: UPDATE public.loct SET a = 2 WHERE ((b = 'foo'::text)) RETURNING a, b +CONTEXT: remote SQL command: UPDATE public.loct SET a = 2 WHERE ((b = 'foo')) RETURNING a, b -- But the reverse is allowed update utrtest set a = 1 where b = 'qux' returning *; ERROR: cannot route tuples into foreign table to be updated "remp" diff --git a/contrib/postgres_fdw/sql/postgres_fdw.sql b/contrib/postgres_fdw/sql/postgres_fdw.sql index 43c30d492d..654db23844 100644 --- a/contrib/postgres_fdw/sql/postgres_fdw.sql +++ b/contrib/postgres_fdw/sql/postgres_fdw.sql @@ -1167,6 +1167,24 @@ SELECT sum(c2), array_agg(c8) FROM ft1 GROUP BY c8; -- ERROR ANALYZE ft1; -- ERROR ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE user_enum; +-- =================================================================== +-- local type can be different from remote type in some cases, +-- in particular if similarly-named operators do equivalent things +-- =================================================================== +ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE text; +EXPLAIN (VERBOSE, COSTS OFF) +SELECT * FROM ft1 WHERE c8 = 'foo' LIMIT 1; +SELECT * FROM ft1 WHERE c8 = 'foo' LIMIT 1; +EXPLAIN (VERBOSE, COSTS OFF) +SELECT * FROM ft1 WHERE 'foo' = c8 LIMIT 1; +SELECT * FROM ft1 WHERE 'foo' = c8 LIMIT 1; +-- we declared c8 to be text locally, but it's still the same type on +-- the remote which will balk if we try to do anything incompatible +-- with that remote type +SELECT * FROM ft1 WHERE c8 LIKE 'foo' LIMIT 1; -- ERROR +SELECT * FROM ft1 WHERE c8::text LIKE 'foo' LIMIT 1; -- ERROR +ALTER FOREIGN TABLE ft1 ALTER COLUMN c8 TYPE user_enum; + -- =================================================================== -- subtransaction -- + local/remote error doesn't break cursor