-- Strings. SELECT '""'::json; -- OK. json ------ "" (1 row) SELECT $$''$$::json; -- ERROR, single quotes are not allowed ERROR: invalid input syntax for type json LINE 1: SELECT $$''$$::json; ^ DETAIL: Token "'" is invalid. CONTEXT: JSON data, line 1: '... SELECT '"abc"'::json; -- OK json ------- "abc" (1 row) SELECT '"abc'::json; -- ERROR, quotes not closed ERROR: invalid input syntax for type json LINE 1: SELECT '"abc'::json; ^ DETAIL: Token ""abc" is invalid. CONTEXT: JSON data, line 1: "abc SELECT '"abc def"'::json; -- ERROR, unescaped newline in string constant ERROR: invalid input syntax for type json LINE 1: SELECT '"abc ^ DETAIL: Character with value 0x0a must be escaped. CONTEXT: JSON data, line 1: "abc SELECT '"\n\"\\"'::json; -- OK, legal escapes json ---------- "\n\"\\" (1 row) SELECT '"\v"'::json; -- ERROR, not a valid JSON escape ERROR: invalid input syntax for type json LINE 1: SELECT '"\v"'::json; ^ DETAIL: Escape sequence "\v" is invalid. CONTEXT: JSON data, line 1: "\v... -- see json_encoding test for input with unicode escapes -- Numbers. SELECT '1'::json; -- OK json ------ 1 (1 row) SELECT '0'::json; -- OK json ------ 0 (1 row) SELECT '01'::json; -- ERROR, not valid according to JSON spec ERROR: invalid input syntax for type json LINE 1: SELECT '01'::json; ^ DETAIL: Token "01" is invalid. CONTEXT: JSON data, line 1: 01 SELECT '0.1'::json; -- OK json ------ 0.1 (1 row) SELECT '9223372036854775808'::json; -- OK, even though it's too large for int8 json --------------------- 9223372036854775808 (1 row) SELECT '1e100'::json; -- OK json ------- 1e100 (1 row) SELECT '1.3e100'::json; -- OK json --------- 1.3e100 (1 row) SELECT '1f2'::json; -- ERROR ERROR: invalid input syntax for type json LINE 1: SELECT '1f2'::json; ^ DETAIL: Token "1f2" is invalid. CONTEXT: JSON data, line 1: 1f2 SELECT '0.x1'::json; -- ERROR ERROR: invalid input syntax for type json LINE 1: SELECT '0.x1'::json; ^ DETAIL: Token "0.x1" is invalid. CONTEXT: JSON data, line 1: 0.x1 SELECT '1.3ex100'::json; -- ERROR ERROR: invalid input syntax for type json LINE 1: SELECT '1.3ex100'::json; ^ DETAIL: Token "1.3ex100" is invalid. CONTEXT: JSON data, line 1: 1.3ex100 -- Arrays. SELECT '[]'::json; -- OK json ------ [] (1 row) SELECT '[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]'::json; -- OK json ---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- [[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[[]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]]] (1 row) SELECT '[1,2]'::json; -- OK json ------- [1,2] (1 row) SELECT '[1,2,]'::json; -- ERROR, trailing comma ERROR: invalid input syntax for type json LINE 1: SELECT '[1,2,]'::json; ^ DETAIL: Expected JSON value, but found "]". CONTEXT: JSON data, line 1: [1,2,] SELECT '[1,2'::json; -- ERROR, no closing bracket ERROR: invalid input syntax for type json LINE 1: SELECT '[1,2'::json; ^ DETAIL: The input string ended unexpectedly. CONTEXT: JSON data, line 1: [1,2 SELECT '[1,[2]'::json; -- ERROR, no closing bracket ERROR: invalid input syntax for type json LINE 1: SELECT '[1,[2]'::json; ^ DETAIL: The input string ended unexpectedly. CONTEXT: JSON data, line 1: [1,[2] -- Objects. SELECT '{}'::json; -- OK json ------ {} (1 row) SELECT '{"abc"}'::json; -- ERROR, no value ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc"}'::json; ^ DETAIL: Expected ":", but found "}". CONTEXT: JSON data, line 1: {"abc"} SELECT '{"abc":1}'::json; -- OK json ----------- {"abc":1} (1 row) SELECT '{1:"abc"}'::json; -- ERROR, keys must be strings ERROR: invalid input syntax for type json LINE 1: SELECT '{1:"abc"}'::json; ^ DETAIL: Expected string or "}", but found "1". CONTEXT: JSON data, line 1: {1... SELECT '{"abc",1}'::json; -- ERROR, wrong separator ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc",1}'::json; ^ DETAIL: Expected ":", but found ",". CONTEXT: JSON data, line 1: {"abc",... SELECT '{"abc"=1}'::json; -- ERROR, totally wrong separator ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc"=1}'::json; ^ DETAIL: Token "=" is invalid. CONTEXT: JSON data, line 1: {"abc"=... SELECT '{"abc"::1}'::json; -- ERROR, another wrong separator ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc"::1}'::json; ^ DETAIL: Expected JSON value, but found ":". CONTEXT: JSON data, line 1: {"abc"::... SELECT '{"abc":1,"def":2,"ghi":[3,4],"hij":{"klm":5,"nop":[6]}}'::json; -- OK json --------------------------------------------------------- {"abc":1,"def":2,"ghi":[3,4],"hij":{"klm":5,"nop":[6]}} (1 row) SELECT '{"abc":1:2}'::json; -- ERROR, colon in wrong spot ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc":1:2}'::json; ^ DETAIL: Expected "," or "}", but found ":". CONTEXT: JSON data, line 1: {"abc":1:... SELECT '{"abc":1,3}'::json; -- ERROR, no value ERROR: invalid input syntax for type json LINE 1: SELECT '{"abc":1,3}'::json; ^ DETAIL: Expected string, but found "3". CONTEXT: JSON data, line 1: {"abc":1,3... -- Recursion. SET max_stack_depth = '100kB'; SELECT repeat('[', 10000)::json; ERROR: stack depth limit exceeded HINT: Increase the configuration parameter "max_stack_depth" (currently 100kB), after ensuring the platform's stack depth limit is adequate. SELECT repeat('{"a":', 10000)::json; ERROR: stack depth limit exceeded HINT: Increase the configuration parameter "max_stack_depth" (currently 100kB), after ensuring the platform's stack depth limit is adequate. RESET max_stack_depth; -- Miscellaneous stuff. SELECT 'true'::json; -- OK json ------ true (1 row) SELECT 'false'::json; -- OK json ------- false (1 row) SELECT 'null'::json; -- OK json ------ null (1 row) SELECT ' true '::json; -- OK, even with extra whitespace json -------- true (1 row) SELECT 'true false'::json; -- ERROR, too many values ERROR: invalid input syntax for type json LINE 1: SELECT 'true false'::json; ^ DETAIL: Expected end of input, but found "false". CONTEXT: JSON data, line 1: true false SELECT 'true, false'::json; -- ERROR, too many values ERROR: invalid input syntax for type json LINE 1: SELECT 'true, false'::json; ^ DETAIL: Expected end of input, but found ",". CONTEXT: JSON data, line 1: true,... SELECT 'truf'::json; -- ERROR, not a keyword ERROR: invalid input syntax for type json LINE 1: SELECT 'truf'::json; ^ DETAIL: Token "truf" is invalid. CONTEXT: JSON data, line 1: truf SELECT 'trues'::json; -- ERROR, not a keyword ERROR: invalid input syntax for type json LINE 1: SELECT 'trues'::json; ^ DETAIL: Token "trues" is invalid. CONTEXT: JSON data, line 1: trues SELECT ''::json; -- ERROR, no value ERROR: invalid input syntax for type json LINE 1: SELECT ''::json; ^ DETAIL: The input string ended unexpectedly. CONTEXT: JSON data, line 1: SELECT ' '::json; -- ERROR, no value ERROR: invalid input syntax for type json LINE 1: SELECT ' '::json; ^ DETAIL: The input string ended unexpectedly. CONTEXT: JSON data, line 1: --constructors -- array_to_json SELECT array_to_json(array(select 1 as a)); array_to_json --------------- [1] (1 row) SELECT array_to_json(array_agg(q),false) from (select x as b, x * 2 as c from generate_series(1,3) x) q; array_to_json --------------------------------------------- [{"b":1,"c":2},{"b":2,"c":4},{"b":3,"c":6}] (1 row) SELECT array_to_json(array_agg(q),true) from (select x as b, x * 2 as c from generate_series(1,3) x) q; array_to_json ----------------- [{"b":1,"c":2},+ {"b":2,"c":4},+ {"b":3,"c":6}] (1 row) SELECT array_to_json(array_agg(q),false) FROM ( SELECT $$a$$ || x AS b, y AS c, ARRAY[ROW(x.*,ARRAY[1,2,3]), ROW(y.*,ARRAY[4,5,6])] AS z FROM generate_series(1,2) x, generate_series(4,5) y) q; array_to_json ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- [{"b":"a1","c":4,"z":[{"f1":1,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]},{"b":"a1","c":5,"z":[{"f1":1,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]},{"b":"a2","c":4,"z":[{"f1":2,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]},{"b":"a2","c":5,"z":[{"f1":2,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]}] (1 row) SELECT array_to_json(array_agg(x),false) from generate_series(5,10) x; array_to_json ---------------- [5,6,7,8,9,10] (1 row) SELECT array_to_json('{{1,5},{99,100}}'::int[]); array_to_json ------------------ [[1,5],[99,100]] (1 row) -- row_to_json SELECT row_to_json(row(1,'foo')); row_to_json --------------------- {"f1":1,"f2":"foo"} (1 row) SELECT row_to_json(q) FROM (SELECT $$a$$ || x AS b, y AS c, ARRAY[ROW(x.*,ARRAY[1,2,3]), ROW(y.*,ARRAY[4,5,6])] AS z FROM generate_series(1,2) x, generate_series(4,5) y) q; row_to_json -------------------------------------------------------------------- {"b":"a1","c":4,"z":[{"f1":1,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]} {"b":"a1","c":5,"z":[{"f1":1,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]} {"b":"a2","c":4,"z":[{"f1":2,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]} {"b":"a2","c":5,"z":[{"f1":2,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]} (4 rows) SELECT row_to_json(q,true) FROM (SELECT $$a$$ || x AS b, y AS c, ARRAY[ROW(x.*,ARRAY[1,2,3]), ROW(y.*,ARRAY[4,5,6])] AS z FROM generate_series(1,2) x, generate_series(4,5) y) q; row_to_json ----------------------------------------------------- {"b":"a1", + "c":4, + "z":[{"f1":1,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]} {"b":"a1", + "c":5, + "z":[{"f1":1,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]} {"b":"a2", + "c":4, + "z":[{"f1":2,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]} {"b":"a2", + "c":5, + "z":[{"f1":2,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]} (4 rows) CREATE TEMP TABLE rows AS SELECT x, 'txt' || x as y FROM generate_series(1,3) AS x; SELECT row_to_json(q,true) FROM rows q; row_to_json -------------- {"x":1, + "y":"txt1"} {"x":2, + "y":"txt2"} {"x":3, + "y":"txt3"} (3 rows) SELECT row_to_json(row((select array_agg(x) as d from generate_series(5,10) x)),false); row_to_json ----------------------- {"f1":[5,6,7,8,9,10]} (1 row) -- to_json, timestamps select to_json(timestamp '2014-05-28 12:22:35.614298'); to_json ------------------------------ "2014-05-28T12:22:35.614298" (1 row) BEGIN; SET LOCAL TIME ZONE 10.5; select to_json(timestamptz '2014-05-28 12:22:35.614298-04'); to_json ------------------------------------ "2014-05-29T02:52:35.614298+10:30" (1 row) SET LOCAL TIME ZONE -8; select to_json(timestamptz '2014-05-28 12:22:35.614298-04'); to_json ------------------------------------ "2014-05-28T08:22:35.614298-08:00" (1 row) COMMIT; select to_json(date '2014-05-28'); to_json -------------- "2014-05-28" (1 row) select to_json(date 'Infinity'); to_json ------------ "infinity" (1 row) select to_json(date '-Infinity'); to_json ------------- "-infinity" (1 row) select to_json(timestamp 'Infinity'); to_json ------------ "infinity" (1 row) select to_json(timestamp '-Infinity'); to_json ------------- "-infinity" (1 row) select to_json(timestamptz 'Infinity'); to_json ------------ "infinity" (1 row) select to_json(timestamptz '-Infinity'); to_json ------------- "-infinity" (1 row) --json_agg SELECT json_agg(q) FROM ( SELECT $$a$$ || x AS b, y AS c, ARRAY[ROW(x.*,ARRAY[1,2,3]), ROW(y.*,ARRAY[4,5,6])] AS z FROM generate_series(1,2) x, generate_series(4,5) y) q; json_agg ----------------------------------------------------------------------- [{"b":"a1","c":4,"z":[{"f1":1,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]}, + {"b":"a1","c":5,"z":[{"f1":1,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]}, + {"b":"a2","c":4,"z":[{"f1":2,"f2":[1,2,3]},{"f1":4,"f2":[4,5,6]}]}, + {"b":"a2","c":5,"z":[{"f1":2,"f2":[1,2,3]},{"f1":5,"f2":[4,5,6]}]}] (1 row) SELECT json_agg(q ORDER BY x, y) FROM rows q; json_agg ----------------------- [{"x":1,"y":"txt1"}, + {"x":2,"y":"txt2"}, + {"x":3,"y":"txt3"}] (1 row) UPDATE rows SET x = NULL WHERE x = 1; SELECT json_agg(q ORDER BY x NULLS FIRST, y) FROM rows q; json_agg -------------------------- [{"x":null,"y":"txt1"}, + {"x":2,"y":"txt2"}, + {"x":3,"y":"txt3"}] (1 row) -- non-numeric output SELECT row_to_json(q) FROM (SELECT 'NaN'::float8 AS "float8field") q; row_to_json ----------------------- {"float8field":"NaN"} (1 row) SELECT row_to_json(q) FROM (SELECT 'Infinity'::float8 AS "float8field") q; row_to_json ---------------------------- {"float8field":"Infinity"} (1 row) SELECT row_to_json(q) FROM (SELECT '-Infinity'::float8 AS "float8field") q; row_to_json ----------------------------- {"float8field":"-Infinity"} (1 row) -- json input SELECT row_to_json(q) FROM (SELECT '{"a":1,"b": [2,3,4,"d","e","f"],"c":{"p":1,"q":2}}'::json AS "jsonfield") q; row_to_json ------------------------------------------------------------------ {"jsonfield":{"a":1,"b": [2,3,4,"d","e","f"],"c":{"p":1,"q":2}}} (1 row) -- json extraction functions CREATE TEMP TABLE test_json ( json_type text, test_json json ); INSERT INTO test_json VALUES ('scalar','"a scalar"'), ('array','["zero", "one","two",null,"four","five", [1,2,3],{"f1":9}]'), ('object','{"field1":"val1","field2":"val2","field3":null, "field4": 4, "field5": [1,2,3], "field6": {"f1":9}}'); SELECT test_json -> 'x' FROM test_json WHERE json_type = 'scalar'; ?column? ---------- (1 row) SELECT test_json -> 'x' FROM test_json WHERE json_type = 'array'; ?column? ---------- (1 row) SELECT test_json -> 'x' FROM test_json WHERE json_type = 'object'; ?column? ---------- (1 row) SELECT test_json->'field2' FROM test_json WHERE json_type = 'object'; ?column? ---------- "val2" (1 row) SELECT test_json->>'field2' FROM test_json WHERE json_type = 'object'; ?column? ---------- val2 (1 row) SELECT test_json -> 2 FROM test_json WHERE json_type = 'scalar'; ?column? ---------- (1 row) SELECT test_json -> 2 FROM test_json WHERE json_type = 'array'; ?column? ---------- "two" (1 row) SELECT test_json -> -1 FROM test_json WHERE json_type = 'array'; ?column? ---------- {"f1":9} (1 row) SELECT test_json -> 2 FROM test_json WHERE json_type = 'object'; ?column? ---------- (1 row) SELECT test_json->>2 FROM test_json WHERE json_type = 'array'; ?column? ---------- two (1 row) SELECT test_json ->> 6 FROM test_json WHERE json_type = 'array'; ?column? ---------- [1,2,3] (1 row) SELECT test_json ->> 7 FROM test_json WHERE json_type = 'array'; ?column? ---------- {"f1":9} (1 row) SELECT test_json ->> 'field4' FROM test_json WHERE json_type = 'object'; ?column? ---------- 4 (1 row) SELECT test_json ->> 'field5' FROM test_json WHERE json_type = 'object'; ?column? ---------- [1,2,3] (1 row) SELECT test_json ->> 'field6' FROM test_json WHERE json_type = 'object'; ?column? ---------- {"f1":9} (1 row) SELECT json_object_keys(test_json) FROM test_json WHERE json_type = 'scalar'; ERROR: cannot call json_object_keys on a scalar SELECT json_object_keys(test_json) FROM test_json WHERE json_type = 'array'; ERROR: cannot call json_object_keys on an array SELECT json_object_keys(test_json) FROM test_json WHERE json_type = 'object'; json_object_keys ------------------ field1 field2 field3 field4 field5 field6 (6 rows) -- test extending object_keys resultset - initial resultset size is 256 select count(*) from (select json_object_keys(json_object(array_agg(g))) from (select unnest(array['f'||n,n::text])as g from generate_series(1,300) as n) x ) y; count ------- 300 (1 row) -- nulls select (test_json->'field3') is null as expect_false from test_json where json_type = 'object'; expect_false -------------- f (1 row) select (test_json->>'field3') is null as expect_true from test_json where json_type = 'object'; expect_true ------------- t (1 row) select (test_json->3) is null as expect_false from test_json where json_type = 'array'; expect_false -------------- f (1 row) select (test_json->>3) is null as expect_true from test_json where json_type = 'array'; expect_true ------------- t (1 row) -- corner cases select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> null::text; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> null::int; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> 1; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> -1; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> 'z'; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json -> ''; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json -> 1; ?column? ------------- {"b": "cc"} (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json -> 3; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json -> 'z'; ?column? ---------- (1 row) select '{"a": "c", "b": null}'::json -> 'b'; ?column? ---------- null (1 row) select '"foo"'::json -> 1; ?column? ---------- (1 row) select '"foo"'::json -> 'z'; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json ->> null::text; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json ->> null::int; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json ->> 1; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json ->> 'z'; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json ->> ''; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json ->> 1; ?column? ------------- {"b": "cc"} (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json ->> 3; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json ->> 'z'; ?column? ---------- (1 row) select '{"a": "c", "b": null}'::json ->> 'b'; ?column? ---------- (1 row) select '"foo"'::json ->> 1; ?column? ---------- (1 row) select '"foo"'::json ->> 'z'; ?column? ---------- (1 row) -- array length SELECT json_array_length('[1,2,3,{"f1":1,"f2":[5,6]},4]'); json_array_length ------------------- 5 (1 row) SELECT json_array_length('[]'); json_array_length ------------------- 0 (1 row) SELECT json_array_length('{"f1":1,"f2":[5,6]}'); ERROR: cannot get array length of a non-array SELECT json_array_length('4'); ERROR: cannot get array length of a scalar -- each select json_each('{"f1":[1,2,3],"f2":{"f3":1},"f4":null}'); json_each ------------------- (f1,"[1,2,3]") (f2,"{""f3"":1}") (f4,null) (3 rows) select * from json_each('{"f1":[1,2,3],"f2":{"f3":1},"f4":null,"f5":99,"f6":"stringy"}') q; key | value -----+----------- f1 | [1,2,3] f2 | {"f3":1} f4 | null f5 | 99 f6 | "stringy" (5 rows) select json_each_text('{"f1":[1,2,3],"f2":{"f3":1},"f4":null,"f5":"null"}'); json_each_text ------------------- (f1,"[1,2,3]") (f2,"{""f3"":1}") (f4,) (f5,null) (4 rows) select * from json_each_text('{"f1":[1,2,3],"f2":{"f3":1},"f4":null,"f5":99,"f6":"stringy"}') q; key | value -----+---------- f1 | [1,2,3] f2 | {"f3":1} f4 | f5 | 99 f6 | stringy (5 rows) -- extract_path, extract_path_as_text select json_extract_path('{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}','f4','f6'); json_extract_path ------------------- "stringy" (1 row) select json_extract_path('{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}','f2'); json_extract_path ------------------- {"f3":1} (1 row) select json_extract_path('{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}','f2',0::text); json_extract_path ------------------- "f3" (1 row) select json_extract_path('{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}','f2',1::text); json_extract_path ------------------- 1 (1 row) select json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}','f4','f6'); json_extract_path_text ------------------------ stringy (1 row) select json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}','f2'); json_extract_path_text ------------------------ {"f3":1} (1 row) select json_extract_path_text('{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}','f2',0::text); json_extract_path_text ------------------------ f3 (1 row) select json_extract_path_text('{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}','f2',1::text); json_extract_path_text ------------------------ 1 (1 row) -- extract_path nulls select json_extract_path('{"f2":{"f3":1},"f4":{"f5":null,"f6":"stringy"}}','f4','f5') is null as expect_false; expect_false -------------- f (1 row) select json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":null,"f6":"stringy"}}','f4','f5') is null as expect_true; expect_true ------------- t (1 row) select json_extract_path('{"f2":{"f3":1},"f4":[0,1,2,null]}','f4','3') is null as expect_false; expect_false -------------- f (1 row) select json_extract_path_text('{"f2":{"f3":1},"f4":[0,1,2,null]}','f4','3') is null as expect_true; expect_true ------------- t (1 row) -- extract_path operators select '{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}'::json#>array['f4','f6']; ?column? ----------- "stringy" (1 row) select '{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}'::json#>array['f2']; ?column? ---------- {"f3":1} (1 row) select '{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}'::json#>array['f2','0']; ?column? ---------- "f3" (1 row) select '{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}'::json#>array['f2','1']; ?column? ---------- 1 (1 row) select '{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}'::json#>>array['f4','f6']; ?column? ---------- stringy (1 row) select '{"f2":{"f3":1},"f4":{"f5":99,"f6":"stringy"}}'::json#>>array['f2']; ?column? ---------- {"f3":1} (1 row) select '{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}'::json#>>array['f2','0']; ?column? ---------- f3 (1 row) select '{"f2":["f3",1],"f4":{"f5":99,"f6":"stringy"}}'::json#>>array['f2','1']; ?column? ---------- 1 (1 row) -- corner cases for same select '{"a": {"b":{"c": "foo"}}}'::json #> '{}'; ?column? --------------------------- {"a": {"b":{"c": "foo"}}} (1 row) select '[1,2,3]'::json #> '{}'; ?column? ---------- [1,2,3] (1 row) select '"foo"'::json #> '{}'; ?column? ---------- "foo" (1 row) select '42'::json #> '{}'; ?column? ---------- 42 (1 row) select 'null'::json #> '{}'; ?column? ---------- null (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a']; ?column? -------------------- {"b":{"c": "foo"}} (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a', null]; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a', '']; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a','b']; ?column? -------------- {"c": "foo"} (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a','b','c']; ?column? ---------- "foo" (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a','b','c','d']; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #> array['a','z','c']; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json #> array['a','1','b']; ?column? ---------- "cc" (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json #> array['a','z','b']; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json #> array['1','b']; ?column? ---------- "cc" (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json #> array['z','b']; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": null}]'::json #> array['1','b']; ?column? ---------- null (1 row) select '"foo"'::json #> array['z']; ?column? ---------- (1 row) select '42'::json #> array['f2']; ?column? ---------- (1 row) select '42'::json #> array['0']; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> '{}'; ?column? --------------------------- {"a": {"b":{"c": "foo"}}} (1 row) select '[1,2,3]'::json #>> '{}'; ?column? ---------- [1,2,3] (1 row) select '"foo"'::json #>> '{}'; ?column? ---------- foo (1 row) select '42'::json #>> '{}'; ?column? ---------- 42 (1 row) select 'null'::json #>> '{}'; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a']; ?column? -------------------- {"b":{"c": "foo"}} (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a', null]; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a', '']; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a','b']; ?column? -------------- {"c": "foo"} (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a','b','c']; ?column? ---------- foo (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a','b','c','d']; ?column? ---------- (1 row) select '{"a": {"b":{"c": "foo"}}}'::json #>> array['a','z','c']; ?column? ---------- (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json #>> array['a','1','b']; ?column? ---------- cc (1 row) select '{"a": [{"b": "c"}, {"b": "cc"}]}'::json #>> array['a','z','b']; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json #>> array['1','b']; ?column? ---------- cc (1 row) select '[{"b": "c"}, {"b": "cc"}]'::json #>> array['z','b']; ?column? ---------- (1 row) select '[{"b": "c"}, {"b": null}]'::json #>> array['1','b']; ?column? ---------- (1 row) select '"foo"'::json #>> array['z']; ?column? ---------- (1 row) select '42'::json #>> array['f2']; ?column? ---------- (1 row) select '42'::json #>> array['0']; ?column? ---------- (1 row) -- array_elements select json_array_elements('[1,true,[1,[2,3]],null,{"f1":1,"f2":[7,8,9]},false,"stringy"]'); json_array_elements ----------------------- 1 true [1,[2,3]] null {"f1":1,"f2":[7,8,9]} false "stringy" (7 rows) select * from json_array_elements('[1,true,[1,[2,3]],null,{"f1":1,"f2":[7,8,9]},false,"stringy"]') q; value ----------------------- 1 true [1,[2,3]] null {"f1":1,"f2":[7,8,9]} false "stringy" (7 rows) select json_array_elements_text('[1,true,[1,[2,3]],null,{"f1":1,"f2":[7,8,9]},false,"stringy"]'); json_array_elements_text -------------------------- 1 true [1,[2,3]] {"f1":1,"f2":[7,8,9]} false stringy (7 rows) select * from json_array_elements_text('[1,true,[1,[2,3]],null,{"f1":1,"f2":[7,8,9]},false,"stringy"]') q; value ----------------------- 1 true [1,[2,3]] {"f1":1,"f2":[7,8,9]} false stringy (7 rows) -- populate_record create type jpop as (a text, b int, c timestamp); select * from json_populate_record(null::jpop,'{"a":"blurfl","x":43.2}') q; a | b | c --------+---+--- blurfl | | (1 row) select * from json_populate_record(row('x',3,'2012-12-31 15:30:56')::jpop,'{"a":"blurfl","x":43.2}') q; a | b | c --------+---+-------------------------- blurfl | 3 | Mon Dec 31 15:30:56 2012 (1 row) select * from json_populate_record(null::jpop,'{"a":"blurfl","x":43.2}') q; a | b | c --------+---+--- blurfl | | (1 row) select * from json_populate_record(row('x',3,'2012-12-31 15:30:56')::jpop,'{"a":"blurfl","x":43.2}') q; a | b | c --------+---+-------------------------- blurfl | 3 | Mon Dec 31 15:30:56 2012 (1 row) select * from json_populate_record(null::jpop,'{"a":[100,200,false],"x":43.2}') q; a | b | c -----------------+---+--- [100,200,false] | | (1 row) select * from json_populate_record(row('x',3,'2012-12-31 15:30:56')::jpop,'{"a":[100,200,false],"x":43.2}') q; a | b | c -----------------+---+-------------------------- [100,200,false] | 3 | Mon Dec 31 15:30:56 2012 (1 row) select * from json_populate_record(row('x',3,'2012-12-31 15:30:56')::jpop,'{"c":[100,200,false],"x":43.2}') q; ERROR: invalid input syntax for type timestamp: "[100,200,false]" -- populate_recordset select * from json_populate_recordset(null::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+---+-------------------------- blurfl | | | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+----+-------------------------- blurfl | 99 | def | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(null::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+---+-------------------------- blurfl | | | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+----+-------------------------- blurfl | 99 | def | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"a":[100,200,300],"x":43.2},{"a":{"z":true},"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c ---------------+----+-------------------------- [100,200,300] | 99 | {"z":true} | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"c":[100,200,300],"x":43.2},{"a":{"z":true},"b":3,"c":"2012-01-20 10:42:53"}]') q; ERROR: invalid input syntax for type timestamp: "[100,200,300]" create type jpop2 as (a int, b json, c int, d int); select * from json_populate_recordset(null::jpop2, '[{"a":2,"c":3,"b":{"z":4},"d":6}]') q; a | b | c | d ---+---------+---+--- 2 | {"z":4} | 3 | 6 (1 row) select * from json_populate_recordset(null::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+---+-------------------------- blurfl | | | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"a":"blurfl","x":43.2},{"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c --------+----+-------------------------- blurfl | 99 | def | 3 | Fri Jan 20 10:42:53 2012 (2 rows) select * from json_populate_recordset(row('def',99,null)::jpop,'[{"a":[100,200,300],"x":43.2},{"a":{"z":true},"b":3,"c":"2012-01-20 10:42:53"}]') q; a | b | c ---------------+----+-------------------------- [100,200,300] | 99 | {"z":true} | 3 | Fri Jan 20 10:42:53 2012 (2 rows) --json_typeof() function select value, json_typeof(value) from (values (json '123.4'), (json '-1'), (json '"foo"'), (json 'true'), (json 'false'), (json 'null'), (json '[1, 2, 3]'), (json '[]'), (json '{"x":"foo", "y":123}'), (json '{}'), (NULL::json)) as data(value); value | json_typeof ----------------------+------------- 123.4 | number -1 | number "foo" | string true | boolean false | boolean null | null [1, 2, 3] | array [] | array {"x":"foo", "y":123} | object {} | object | (11 rows) -- json_build_array, json_build_object, json_object_agg SELECT json_build_array('a',1,'b',1.2,'c',true,'d',null,'e',json '{"x": 3, "y": [1,2,3]}'); json_build_array ----------------------------------------------------------------------- ["a", 1, "b", 1.2, "c", true, "d", null, "e", {"x": 3, "y": [1,2,3]}] (1 row) SELECT json_build_object('a',1,'b',1.2,'c',true,'d',null,'e',json '{"x": 3, "y": [1,2,3]}'); json_build_object ---------------------------------------------------------------------------- {"a" : 1, "b" : 1.2, "c" : true, "d" : null, "e" : {"x": 3, "y": [1,2,3]}} (1 row) SELECT json_build_object( 'a', json_build_object('b',false,'c',99), 'd', json_build_object('e',array[9,8,7]::int[], 'f', (select row_to_json(r) from ( select relkind, oid::regclass as name from pg_class where relname = 'pg_class') r))); json_build_object ------------------------------------------------------------------------------------------------- {"a" : {"b" : false, "c" : 99}, "d" : {"e" : [9,8,7], "f" : {"relkind":"r","name":"pg_class"}}} (1 row) -- empty objects/arrays SELECT json_build_array(); json_build_array ------------------ [] (1 row) SELECT json_build_object(); json_build_object ------------------- {} (1 row) -- make sure keys are quoted SELECT json_build_object(1,2); json_build_object ------------------- {"1" : 2} (1 row) -- keys must be scalar and not null SELECT json_build_object(null,2); ERROR: argument 1 cannot be null HINT: Object keys should be text. SELECT json_build_object(r,2) FROM (SELECT 1 AS a, 2 AS b) r; ERROR: key value must be scalar, not array, composite, or json SELECT json_build_object(json '{"a":1,"b":2}', 3); ERROR: key value must be scalar, not array, composite, or json SELECT json_build_object('{1,2,3}'::int[], 3); ERROR: key value must be scalar, not array, composite, or json CREATE TEMP TABLE foo (serial_num int, name text, type text); INSERT INTO foo VALUES (847001,'t15','GE1043'); INSERT INTO foo VALUES (847002,'t16','GE1043'); INSERT INTO foo VALUES (847003,'sub-alpha','GESS90'); SELECT json_build_object('turbines',json_object_agg(serial_num,json_build_object('name',name,'type',type))) FROM foo; json_build_object ------------------------------------------------------------------------------------------------------------------------------------------------------------------------- {"turbines" : { "847001" : {"name" : "t15", "type" : "GE1043"}, "847002" : {"name" : "t16", "type" : "GE1043"}, "847003" : {"name" : "sub-alpha", "type" : "GESS90"} }} (1 row) SELECT json_object_agg(name, type) FROM foo; json_object_agg ---------------------------------------------------------------- { "t15" : "GE1043", "t16" : "GE1043", "sub-alpha" : "GESS90" } (1 row) INSERT INTO foo VALUES (999999, NULL, 'bar'); SELECT json_object_agg(name, type) FROM foo; ERROR: field name must not be null -- json_object -- empty object, one dimension SELECT json_object('{}'); json_object ------------- {} (1 row) -- empty object, two dimensions SELECT json_object('{}', '{}'); json_object ------------- {} (1 row) -- one dimension SELECT json_object('{a,1,b,2,3,NULL,"d e f","a b c"}'); json_object ------------------------------------------------------- {"a" : "1", "b" : "2", "3" : null, "d e f" : "a b c"} (1 row) -- same but with two dimensions SELECT json_object('{{a,1},{b,2},{3,NULL},{"d e f","a b c"}}'); json_object ------------------------------------------------------- {"a" : "1", "b" : "2", "3" : null, "d e f" : "a b c"} (1 row) -- odd number error SELECT json_object('{a,b,c}'); ERROR: array must have even number of elements -- one column error SELECT json_object('{{a},{b}}'); ERROR: array must have two columns -- too many columns error SELECT json_object('{{a,b,c},{b,c,d}}'); ERROR: array must have two columns -- too many dimensions error SELECT json_object('{{{a,b},{c,d}},{{b,c},{d,e}}}'); ERROR: wrong number of array subscripts --two argument form of json_object select json_object('{a,b,c,"d e f"}','{1,2,3,"a b c"}'); json_object ------------------------------------------------------ {"a" : "1", "b" : "2", "c" : "3", "d e f" : "a b c"} (1 row) -- too many dimensions SELECT json_object('{{a,1},{b,2},{3,NULL},{"d e f","a b c"}}', '{{a,1},{b,2},{3,NULL},{"d e f","a b c"}}'); ERROR: wrong number of array subscripts -- mismatched dimensions select json_object('{a,b,c,"d e f",g}','{1,2,3,"a b c"}'); ERROR: mismatched array dimensions select json_object('{a,b,c,"d e f"}','{1,2,3,"a b c",g}'); ERROR: mismatched array dimensions -- null key error select json_object('{a,b,NULL,"d e f"}','{1,2,3,"a b c"}'); ERROR: null value not allowed for object key -- empty key is allowed select json_object('{a,b,"","d e f"}','{1,2,3,"a b c"}'); json_object ----------------------------------------------------- {"a" : "1", "b" : "2", "" : "3", "d e f" : "a b c"} (1 row) -- json_to_record and json_to_recordset select * from json_to_record('{"a":1,"b":"foo","c":"bar"}') as x(a int, b text, d text); a | b | d ---+-----+--- 1 | foo | (1 row) select * from json_to_recordset('[{"a":1,"b":"foo","d":false},{"a":2,"b":"bar","c":true}]') as x(a int, b text, c boolean); a | b | c ---+-----+--- 1 | foo | 2 | bar | t (2 rows) select * from json_to_recordset('[{"a":1,"b":{"d":"foo"},"c":true},{"a":2,"c":false,"b":{"d":"bar"}}]') as x(a int, b json, c boolean); a | b | c ---+-------------+--- 1 | {"d":"foo"} | t 2 | {"d":"bar"} | f (2 rows) select *, c is null as c_is_null from json_to_record('{"a":1, "b":{"c":16, "d":2}, "x":8}'::json) as t(a int, b json, c text, x int); a | b | c | x | c_is_null ---+-----------------+---+---+----------- 1 | {"c":16, "d":2} | | 8 | t (1 row) select *, c is null as c_is_null from json_to_recordset('[{"a":1, "b":{"c":16, "d":2}, "x":8}]'::json) as t(a int, b json, c text, x int); a | b | c | x | c_is_null ---+-----------------+---+---+----------- 1 | {"c":16, "d":2} | | 8 | t (1 row) -- json_strip_nulls select json_strip_nulls(null); json_strip_nulls ------------------ (1 row) select json_strip_nulls('1'); json_strip_nulls ------------------ 1 (1 row) select json_strip_nulls('"a string"'); json_strip_nulls ------------------ "a string" (1 row) select json_strip_nulls('null'); json_strip_nulls ------------------ null (1 row) select json_strip_nulls('[1,2,null,3,4]'); json_strip_nulls ------------------ [1,2,null,3,4] (1 row) select json_strip_nulls('{"a":1,"b":null,"c":[2,null,3],"d":{"e":4,"f":null}}'); json_strip_nulls ------------------------------------ {"a":1,"c":[2,null,3],"d":{"e":4}} (1 row) select json_strip_nulls('[1,{"a":1,"b":null,"c":2},3]'); json_strip_nulls --------------------- [1,{"a":1,"c":2},3] (1 row) -- an empty object is not null and should not be stripped select json_strip_nulls('{"a": {"b": null, "c": null}, "d": {} }'); json_strip_nulls ------------------ {"a":{},"d":{}} (1 row)