Movatterモバイル変換

json->integer →json

jsonb->integer →jsonb

Extractsn'th element of JSON array (array elements are indexed from zero, but negative integers count from the end).

'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -> 2 →{"c":"baz"}

'[{"a":"foo"},{"b":"bar"},{"c":"baz"}]'::json -> -3 →{"a":"foo"}

json->text →json

jsonb->text →jsonb

Extracts JSON object field with the given key.

'{"a": {"b":"foo"}}'::json -> 'a' →{"b":"foo"}

json->>integer →text

jsonb->>integer →text

Extractsn'th element of JSON array, astext.

'[1,2,3]'::json ->> 2 →3

json->>text →text

jsonb->>text →text

Extracts JSON object field with the given key, astext.

'{"a":1,"b":2}'::json ->> 'b' →2

json#>text[] →json

jsonb#>text[] →jsonb

Extracts JSON sub-object at the specified path, where path elements can be either field keys or array indexes.

'{"a": {"b": ["foo","bar"]}}'::json #> '{a,b,1}' →"bar"

json#>>text[] →text

jsonb#>>text[] →text

Extracts JSON sub-object at the specified path astext.

'{"a": {"b": ["foo","bar"]}}'::json #>> '{a,b,1}' →bar

jsonb@>jsonb →boolean

Does the first JSON value contain the second? (SeeSection 8.14.3 for details about containment.)

'{"a":1, "b":2}'::jsonb @> '{"b":2}'::jsonb →t

jsonb<@jsonb →boolean

Is the first JSON value contained in the second?

'{"b":2}'::jsonb <@ '{"a":1, "b":2}'::jsonb →t

jsonb?text →boolean

Does the text string exist as a top-level key or array element within the JSON value?

'{"a":1, "b":2}'::jsonb ? 'b' →t

'["a", "b", "c"]'::jsonb ? 'b' →t

jsonb?|text[] →boolean

Do any of the strings in the text array exist as top-level keys or array elements?

'{"a":1, "b":2, "c":3}'::jsonb ?| array['b', 'd'] →t

jsonb?&text[] →boolean

Do all of the strings in the text array exist as top-level keys or array elements?

'["a", "b", "c"]'::jsonb ?& array['a', 'b'] →t

jsonb||jsonb →jsonb

Concatenates twojsonb values. Concatenating two arrays generates an array containing all the elements of each input. Concatenating two objects generates an object containing the union of their keys, taking the second object's value when there are duplicate keys. All other cases are treated by converting a non-array input into a single-element array, and then proceeding as for two arrays. Does not operate recursively: only the top-level array or object structure is merged.

'["a", "b"]'::jsonb || '["a", "d"]'::jsonb →["a", "b", "a", "d"]

'{"a": "b"}'::jsonb || '{"c": "d"}'::jsonb →{"a": "b", "c": "d"}

'[1, 2]'::jsonb || '3'::jsonb →[1, 2, 3]

'{"a": "b"}'::jsonb || '42'::jsonb →[{"a": "b"}, 42]

To append an array to another array as a single entry, wrap it in an additional layer of array, for example:

'[1, 2]'::jsonb || jsonb_build_array('[3, 4]'::jsonb) →[1, 2, [3, 4]]

jsonb-text →jsonb

Deletes a key (and its value) from a JSON object, or matching string value(s) from a JSON array.

'{"a": "b", "c": "d"}'::jsonb - 'a' →{"c": "d"}

'["a", "b", "c", "b"]'::jsonb - 'b' →["a", "c"]

jsonb-text[] →jsonb

Deletes all matching keys or array elements from the left operand.

'{"a": "b", "c": "d"}'::jsonb - '{a,c}'::text[] →{}

jsonb-integer →jsonb

Deletes the array element with specified index (negative integers count from the end). Throws an error if JSON value is not an array.

'["a", "b"]'::jsonb - 1 →["a"]

jsonb#-text[] →jsonb

Deletes the field or array element at the specified path, where path elements can be either field keys or array indexes.

'["a", {"b":1}]'::jsonb #- '{1,b}' →["a", {}]

jsonb@?jsonpath →boolean

Does JSON path return any item for the specified JSON value?

'{"a":[1,2,3,4,5]}'::jsonb @? '$.a[*] ? (@ > 2)' →t

jsonb@@jsonpath →boolean

Returns the result of a JSON path predicate check for the specified JSON value. Only the first item of the result is taken into account. If the result is not Boolean, thenNULL is returned.

'{"a":[1,2,3,4,5]}'::jsonb @@ '$.a[*] > 2' →t

to_json (anyelement ) →json

to_jsonb (anyelement ) →jsonb

Converts any SQL value tojson orjsonb. Arrays and composites are converted recursively to arrays and objects (multidimensional arrays become arrays of arrays in JSON). Otherwise, if there is a cast from the SQL data type tojson, the cast function will be used to perform the conversion;^[a] otherwise, a scalar JSON value is produced. For any scalar other than a number, a Boolean, or a null value, the text representation will be used, with escaping as necessary to make it a valid JSON string value.

to_json('Fred said "Hi."'::text) →"Fred said \"Hi.\""

to_jsonb(row(42, 'Fred said "Hi."'::text)) →{"f1": 42, "f2": "Fred said \"Hi.\""}

array_to_json (anyarray [,boolean] ) →json

Converts an SQL array to a JSON array. The behavior is the same asto_json except that line feeds will be added between top-level array elements if the optional boolean parameter is true.

array_to_json('{{1,5},{99,100}}'::int[]) →[[1,5],[99,100]]

json_array ( [ {value_expression [FORMAT JSON] } [, ...]] [ {NULL |ABSENT }ON NULL] [RETURNINGdata_type [FORMAT JSON [ENCODING UTF8]]])

json_array ( [query_expression] [RETURNINGdata_type [FORMAT JSON [ENCODING UTF8]]])

Constructs a JSON array from either a series ofvalue_expression parameters or from the results ofquery_expression, which must be a SELECT query returning a single column. IfABSENT ON NULL is specified, NULL values are ignored. This is always the case if aquery_expression is used.

json_array(1,true,json '{"a":null}') →[1, true, {"a":null}]

json_array(SELECT * FROM (VALUES(1),(2)) t) →[1, 2]

row_to_json (record [,boolean] ) →json

Converts an SQL composite value to a JSON object. The behavior is the same asto_json except that line feeds will be added between top-level elements if the optional boolean parameter is true.

row_to_json(row(1,'foo')) →{"f1":1,"f2":"foo"}

json_build_array (VARIADIC"any" ) →json

jsonb_build_array (VARIADIC"any" ) →jsonb

Builds a possibly-heterogeneously-typed JSON array out of a variadic argument list. Each argument is converted as perto_json orto_jsonb.

json_build_array(1, 2, 'foo', 4, 5) →[1, 2, "foo", 4, 5]

json_build_object (VARIADIC"any" ) →json

jsonb_build_object (VARIADIC"any" ) →jsonb

Builds a JSON object out of a variadic argument list. By convention, the argument list consists of alternating keys and values. Key arguments are coerced to text; value arguments are converted as perto_json orto_jsonb.

json_build_object('foo', 1, 2, row(3,'bar')) →{"foo" : 1, "2" : {"f1":3,"f2":"bar"}}

json_object ( [ {key_expression {VALUE | ':' }value_expression [FORMAT JSON [ENCODING UTF8]] }[, ...]] [ {NULL |ABSENT }ON NULL] [ {WITH |WITHOUT }UNIQUE [KEYS]] [RETURNINGdata_type [FORMAT JSON [ENCODING UTF8]]])

Constructs a JSON object of all the key/value pairs given, or an empty object if none are given.key_expression is a scalar expression defining theJSON key, which is converted to thetext type. It cannot beNULL nor can it belong to a type that has a cast to thejson type. IfWITH UNIQUE KEYS is specified, there must not be any duplicatekey_expression. Any pair for which thevalue_expression evaluates toNULL is omitted from the output ifABSENT ON NULL is specified; ifNULL ON NULL is specified or the clause omitted, the key is included with valueNULL.

json_object('code' VALUE 'P123', 'title': 'Jaws') →{"code" : "P123", "title" : "Jaws"}

json_object (text[] ) →json

jsonb_object (text[] ) →jsonb

Builds a JSON object out of a text array. The array must have either exactly one dimension with an even number of members, in which case they are taken as alternating key/value pairs, or two dimensions such that each inner array has exactly two elements, which are taken as a key/value pair. All values are converted to JSON strings.

json_object('{a, 1, b, "def", c, 3.5}') →{"a" : "1", "b" : "def", "c" : "3.5"}

json_object('{{a, 1}, {b, "def"}, {c, 3.5}}') →{"a" : "1", "b" : "def", "c" : "3.5"}

json_object (keystext[],valuestext[] ) →json

jsonb_object (keystext[],valuestext[] ) →jsonb

This form ofjson_object takes keys and values pairwise from separate text arrays. Otherwise it is identical to the one-argument form.

json_object('{a,b}', '{1,2}') →{"a": "1", "b": "2"}

json (expression [FORMAT JSON [ENCODING UTF8]] [ {WITH |WITHOUT }UNIQUE [KEYS]]

Converts a given expression specified astext orbytea string (in UTF8 encoding) into a JSON value. Ifexpression is NULL, anSQL null value is returned. IfWITH UNIQUE is specified, theexpression must not contain any duplicate object keys.

json('{"a":123, "b":[true,"foo"], "a":"bar"}') →{"a":123, "b":[true,"foo"], "a":"bar"}

json_scalar (expression)

Converts a given SQL scalar value into a JSON scalar value. If the input is NULL, anSQL null is returned. If the input is number or a boolean value, a corresponding JSON number or boolean value is returned. For any other value, a JSON string is returned.

json_scalar(123.45) →123.45

json_scalar(CURRENT_TIMESTAMP) →"2022-05-10T10:51:04.62128-04:00"

json_serialize (expression [FORMAT JSON [ENCODING UTF8]] [RETURNINGdata_type [FORMAT JSON [ENCODING UTF8]]])

Converts an SQL/JSON expression into a character or binary string. Theexpression can be of any JSON type, any character string type, orbytea in UTF8 encoding. The returned type used in RETURNING can be any character string type orbytea. The default istext.

json_serialize('{ "a" : 1 } ' RETURNING bytea) →\x7b20226122203a2031207d20

expressionIS [NOT]JSON [ {VALUE |SCALAR |ARRAY |OBJECT }] [ {WITH |WITHOUT }UNIQUE [KEYS]]

This predicate tests whetherexpression can be parsed as JSON, possibly of a specified type. IfSCALAR orARRAY orOBJECT is specified, the test is whether or not the JSON is of that particular type. IfWITH UNIQUE KEYS is specified, then any object in theexpression is also tested to see if it has duplicate keys.

SELECT js,  js IS JSON "json?",  js IS JSON SCALAR "scalar?",  js IS JSON OBJECT "object?",  js IS JSON ARRAY "array?"FROM (VALUES      ('123'), ('"abc"'), ('{"a": "b"}'), ('[1,2]'),('abc')) foo(js);     js     | json? | scalar? | object? | array?------------+-------+---------+---------+-------- 123        | t     | t       | f       | f "abc"      | t     | t       | f       | f {"a": "b"} | t     | f       | t       | f [1,2]      | t     | f       | f       | t abc        | f     | f       | f       | f

SELECT js,  js IS JSON OBJECT "object?",  js IS JSON ARRAY "array?",  js IS JSON ARRAY WITH UNIQUE KEYS "array w. UK?",  js IS JSON ARRAY WITHOUT UNIQUE KEYS "array w/o UK?"FROM (VALUES ('[{"a":"1"}, {"b":"2","b":"3"}]')) foo(js);-[ RECORD 1 ]-+--------------------js            | [{"a":"1"},        +              |  {"b":"2","b":"3"}]object?       | farray?        | tarray w. UK?  | farray w/o UK? | t

json_array_elements (json ) →setof json

jsonb_array_elements (jsonb ) →setof jsonb

Expands the top-level JSON array into a set of JSON values.

select * from json_array_elements('[1,true, [2,false]]') →

   value----------- 1 true [2,false]

json_array_elements_text (json ) →setof text

jsonb_array_elements_text (jsonb ) →setof text

Expands the top-level JSON array into a set oftext values.

select * from json_array_elements_text('["foo", "bar"]') →

   value----------- foo bar

json_array_length (json ) →integer

jsonb_array_length (jsonb ) →integer

Returns the number of elements in the top-level JSON array.

json_array_length('[1,2,3,{"f1":1,"f2":[5,6]},4]') →5

jsonb_array_length('[]') →0

json_each (json ) →setof record (keytext,valuejson )

jsonb_each (jsonb ) →setof record (keytext,valuejsonb )

Expands the top-level JSON object into a set of key/value pairs.

select * from json_each('{"a":"foo", "b":"bar"}') →

 key | value-----+------- a   | "foo" b   | "bar"

json_each_text (json ) →setof record (keytext,valuetext )

jsonb_each_text (jsonb ) →setof record (keytext,valuetext )

Expands the top-level JSON object into a set of key/value pairs. The returnedvalues will be of typetext.

select * from json_each_text('{"a":"foo", "b":"bar"}') →

 key | value-----+------- a   | foo b   | bar

json_extract_path (from_jsonjson,VARIADICpath_elemstext[] ) →json

jsonb_extract_path (from_jsonjsonb,VARIADICpath_elemstext[] ) →jsonb

Extracts JSON sub-object at the specified path. (This is functionally equivalent to the#> operator, but writing the path out as a variadic list can be more convenient in some cases.)

json_extract_path('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6') →"foo"

json_extract_path_text (from_jsonjson,VARIADICpath_elemstext[] ) →text

jsonb_extract_path_text (from_jsonjsonb,VARIADICpath_elemstext[] ) →text

Extracts JSON sub-object at the specified path astext. (This is functionally equivalent to the#>> operator.)

json_extract_path_text('{"f2":{"f3":1},"f4":{"f5":99,"f6":"foo"}}', 'f4', 'f6') →foo

json_object_keys (json ) →setof text

jsonb_object_keys (jsonb ) →setof text

Returns the set of keys in the top-level JSON object.

select * from json_object_keys('{"f1":"abc","f2":{"f3":"a", "f4":"b"}}') →

 json_object_keys------------------ f1 f2

json_populate_record (baseanyelement,from_jsonjson ) →anyelement

jsonb_populate_record (baseanyelement,from_jsonjsonb ) →anyelement

Expands the top-level JSON object to a row having the composite type of thebase argument. The JSON object is scanned for fields whose names match column names of the output row type, and their values are inserted into those columns of the output. (Fields that do not correspond to any output column name are ignored.) In typical use, the value ofbase is justNULL, which means that any output columns that do not match any object field will be filled with nulls. However, ifbase isn'tNULL then the values it contains will be used for unmatched columns.

To convert a JSON value to the SQL type of an output column, the following rules are applied in sequence:

While the example below uses a constant JSON value, typical use would be to reference ajson orjsonb column laterally from another table in the query'sFROM clause. Writingjson_populate_record in theFROM clause is good practice, since all of the extracted columns are available for use without duplicate function calls.

create type subrowtype as (d int, e text);create type myrowtype as (a int, b text[], c subrowtype);

select * from json_populate_record(null::myrowtype, '{"a": 1, "b": ["2", "a b"], "c": {"d": 4, "e": "a b c"}, "x": "foo"}') →

 a |   b       |      c---+-----------+------------- 1 | {2,"a b"} | (4,"a b c")

json_populate_recordset (baseanyelement,from_jsonjson ) →setof anyelement

jsonb_populate_recordset (baseanyelement,from_jsonjsonb ) →setof anyelement

Expands the top-level JSON array of objects to a set of rows having the composite type of thebase argument. Each element of the JSON array is processed as described above forjson[b]_populate_record.

create type twoints as (a int, b int);

select * from json_populate_recordset(null::twoints, '[{"a":1,"b":2}, {"a":3,"b":4}]') →

 a | b---+--- 1 | 2 3 | 4

json_to_record (json ) →record

jsonb_to_record (jsonb ) →record

Expands the top-level JSON object to a row having the composite type defined by anAS clause. (As with all functions returningrecord, the calling query must explicitly define the structure of the record with anAS clause.) The output record is filled from fields of the JSON object, in the same way as described above forjson[b]_populate_record. Since there is no input record value, unmatched columns are always filled with nulls.

create type myrowtype as (a int, b text);

select * from json_to_record('{"a":1,"b":[1,2,3],"c":[1,2,3],"e":"bar","r": {"a": 123, "b": "a b c"}}') as x(a int, b text, c int[], d text, r myrowtype) →

 a |    b    |    c    | d |       r---+---------+---------+---+--------------- 1 | [1,2,3] | {1,2,3} |   | (123,"a b c")

json_to_recordset (json ) →setof record

jsonb_to_recordset (jsonb ) →setof record

Expands the top-level JSON array of objects to a set of rows having the composite type defined by anAS clause. (As with all functions returningrecord, the calling query must explicitly define the structure of the record with anAS clause.) Each element of the JSON array is processed as described above forjson[b]_populate_record.

select * from json_to_recordset('[{"a":1,"b":"foo"}, {"a":"2","c":"bar"}]') as x(a int, b text) →

 a |  b---+----- 1 | foo 2 |

jsonb_set (targetjsonb,pathtext[],new_valuejsonb [,create_if_missingboolean] ) →jsonb

Returnstarget with the item designated bypath replaced bynew_value, or withnew_value added ifcreate_if_missing is true (which is the default) and the item designated bypath does not exist. All earlier steps in the path must exist, or thetarget is returned unchanged. As with the path oriented operators, negative integers that appear in thepath count from the end of JSON arrays. If the last path step is an array index that is out of range, andcreate_if_missing is true, the new value is added at the beginning of the array if the index is negative, or at the end of the array if it is positive.

jsonb_set('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', '[2,3,4]', false) →[{"f1": [2, 3, 4], "f2": null}, 2, null, 3]

jsonb_set('[{"f1":1,"f2":null},2]', '{0,f3}', '[2,3,4]') →[{"f1": 1, "f2": null, "f3": [2, 3, 4]}, 2]

jsonb_set_lax (targetjsonb,pathtext[],new_valuejsonb [,create_if_missingboolean [,null_value_treatmenttext]] ) →jsonb

Ifnew_value is notNULL, behaves identically tojsonb_set. Otherwise behaves according to the value ofnull_value_treatment which must be one of'raise_exception','use_json_null','delete_key', or'return_target'. The default is'use_json_null'.

jsonb_set_lax('[{"f1":1,"f2":null},2,null,3]', '{0,f1}', null) →[{"f1": null, "f2": null}, 2, null, 3]

jsonb_set_lax('[{"f1":99,"f2":null},2]', '{0,f3}', null, true, 'return_target') →[{"f1": 99, "f2": null}, 2]

jsonb_insert (targetjsonb,pathtext[],new_valuejsonb [,insert_afterboolean] ) →jsonb

Returnstarget withnew_value inserted. If the item designated by thepath is an array element,new_value will be inserted before that item ifinsert_after is false (which is the default), or after it ifinsert_after is true. If the item designated by thepath is an object field,new_value will be inserted only if the object does not already contain that key. All earlier steps in the path must exist, or thetarget is returned unchanged. As with the path oriented operators, negative integers that appear in thepath count from the end of JSON arrays. If the last path step is an array index that is out of range, the new value is added at the beginning of the array if the index is negative, or at the end of the array if it is positive.

jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"') →{"a": [0, "new_value", 1, 2]}

jsonb_insert('{"a": [0,1,2]}', '{a, 1}', '"new_value"', true) →{"a": [0, 1, "new_value", 2]}

json_strip_nulls (json ) →json

jsonb_strip_nulls (jsonb ) →jsonb

Deletes all object fields that have null values from the given JSON value, recursively. Null values that are not object fields are untouched.

json_strip_nulls('[{"f1":1, "f2":null}, 2, null, 3]') →[{"f1":1},2,null,3]

jsonb_path_exists (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →boolean

Checks whether the JSON path returns any item for the specified JSON value. If thevars argument is specified, it must be a JSON object, and its fields provide named values to be substituted into thejsonpath expression. If thesilent argument is specified and istrue, the function suppresses the same errors as the@? and@@ operators do.

jsonb_path_exists('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}') →t

jsonb_path_match (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →boolean

Returns the result of a JSON path predicate check for the specified JSON value. Only the first item of the result is taken into account. If the result is not Boolean, thenNULL is returned. The optionalvars andsilent arguments act the same as forjsonb_path_exists.

jsonb_path_match('{"a":[1,2,3,4,5]}', 'exists($.a[*] ? (@ >= $min && @ <= $max))', '{"min":2, "max":4}') →t

jsonb_path_query (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →setof jsonb

Returns all JSON items returned by the JSON path for the specified JSON value. The optionalvars andsilent arguments act the same as forjsonb_path_exists.

select * from jsonb_path_query('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}') →

 jsonb_path_query------------------ 2 3 4

jsonb_path_query_array (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →jsonb

Returns all JSON items returned by the JSON path for the specified JSON value, as a JSON array. The optionalvars andsilent arguments act the same as forjsonb_path_exists.

jsonb_path_query_array('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}') →[2, 3, 4]

jsonb_path_query_first (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →jsonb

Returns the first JSON item returned by the JSON path for the specified JSON value. ReturnsNULL if there are no results. The optionalvars andsilent arguments act the same as forjsonb_path_exists.

jsonb_path_query_first('{"a":[1,2,3,4,5]}', '$.a[*] ? (@ >= $min && @ <= $max)', '{"min":2, "max":4}') →2

jsonb_path_exists_tz (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →boolean

jsonb_path_match_tz (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →boolean

jsonb_path_query_tz (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →setof jsonb

jsonb_path_query_array_tz (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →jsonb

jsonb_path_query_first_tz (targetjsonb,pathjsonpath [,varsjsonb [,silentboolean]] ) →jsonb

These functions act like their counterparts described above without the_tz suffix, except that these functions support comparisons of date/time values that require timezone-aware conversions. The example below requires interpretation of the date-only value2015-08-02 as a timestamp with time zone, so the result depends on the currentTimeZone setting. Due to this dependency, these functions are marked as stable, which means these functions cannot be used in indexes. Their counterparts are immutable, and so can be used in indexes; but they will throw errors if asked to make such comparisons.

jsonb_path_exists_tz('["2015-08-01 12:00:00-05"]', '$[*] ? (@.datetime() < "2015-08-02".datetime())') →t

jsonb_pretty (jsonb ) →text

Converts the given JSON value to pretty-printed, indented text.

jsonb_pretty('[{"f1":1,"f2":null}, 2]') →

[    {        "f1": 1,        "f2": null    },    2]

json_typeof (json ) →text

jsonb_typeof (jsonb ) →text

Returns the type of the top-level JSON value as a text string. Possible types areobject,array,string,number,boolean, andnull. (Thenull result should not be confused with an SQL NULL; see the examples.)

json_typeof('-123.4') →number

json_typeof('null'::json) →null

json_typeof(NULL::json) IS NULL →t

json_exists (context_item,path_expression [PASSING {valueASvarname } [, ...]] [RETURNINGdata_type] [ {TRUE |FALSE | UNKNOWN |ERROR }ON ERROR])

Returns true if the SQL/JSONpath_expression applied to thecontext_item using thevalues yields any items. TheON ERROR clause specifies what is returned if an error occurs; the default is to returnFALSE. Note that if thepath_expression isstrict, an error is generated if it yields no items.

json_exists(jsonb '{"key1": [1,2,3]}', 'strict $.key1[*] ? (@ > 2)') →t

json_exists(jsonb '{"a": [1,2,3]}', 'lax $.a[5]' ERROR ON ERROR) →f

json_exists(jsonb '{"a": [1,2,3]}', 'strict $.a[5]' ERROR ON ERROR) →ERROR: jsonpath array subscript is out of bounds

json_query (context_item,path_expression [PASSING {valueASvarname } [, ...]] [RETURNINGdata_type [FORMAT JSON [ENCODING UTF8]]] [ {WITHOUT |WITH {CONDITIONAL | [UNCONDITIONAL] } } [ARRAY]WRAPPER] [ {KEEP |OMIT }QUOTES [ON SCALAR STRING]] [ {ERROR |NULL |EMPTY { [ARRAY] |OBJECT } |DEFAULTexpression }ON EMPTY] [ {ERROR |NULL |EMPTY { [ARRAY] |OBJECT } |DEFAULTexpression }ON ERROR])

Returns the result of applying thepath_expression to thecontext_item using thevalues. This function must return a JSON string, so if the path expression returns multiple SQL/JSON items, you must wrap the result using theWITH WRAPPER clause. If the wrapper isUNCONDITIONAL, an array wrapper will always be applied, even if the returned value is already a single JSON object or array, but if it isCONDITIONAL, it will not be applied to a single array or object.UNCONDITIONAL is the default. If the result is a scalar string, by default the value returned will have surrounding quotes making it a valid JSON value, which can be made explicit by specifyingKEEP QUOTES. Conversely, quotes can be omitted by specifyingOMIT QUOTES. The returneddata_type has the same semantics as for constructor functions likejson_objectagg; the default returned type isjsonb. TheON EMPTY clause specifies the behavior if thepath_expression yields no value at all; the default whenON EMPTY is not specified is to return a null value. TheON ERROR clause specifies the behavior if an error occurs as a result ofjsonpath evaluation (including cast to the output type) or during the execution ofON EMPTY behavior (that was caused by empty result ofjsonpath evaluation); the default whenON ERROR is not specified is to return a null value.

json_query(jsonb '[1,[2,3],null]', 'lax $[*][1]' WITH CONDITIONAL WRAPPER) →[3]

json_value (context_item,path_expression [PASSING {valueASvarname } [, ...]] [RETURNINGdata_type] [ {ERROR |NULL |DEFAULTexpression }ON EMPTY] [ {ERROR |NULL |DEFAULTexpression }ON ERROR])

Returns the result of applying thepath_expression to thecontext_item using thePASSINGvalues. The extracted value must be a singleSQL/JSON scalar item. For results that are objects or arrays, use thejson_query function instead. The returneddata_type has the same semantics as for constructor functions likejson_objectagg. The default returned type istext. TheON ERROR andON EMPTY clauses have similar semantics as mentioned in the description ofjson_query.

json_value(jsonb '"123.45"', '$' RETURNING float) →123.45

json_value(jsonb '"03:04 2015-02-01"', '$.datetime("HH24:MI YYYY-MM-DD")' RETURNING date) →2015-02-01

json_value(jsonb '[1,2]', 'strict $[*]' DEFAULT 9 ON ERROR) →9