selectarray_to_json(array_agg(row_to_json(t)))from(selectid, textfromwords ) t This will result in a JSON array of objects: [{"id":6001,"text":"abaissed"},{"id":6002,"text":"abbatial"},{"id":6003,"text":"abelia"},...] In exchange for a substantial jump in complexity, ...
extract array elements, object fields, get the length of arrays and the set of keys of a field, deconstruct an object into a set of key/value pairs, and create records from JSON objects and arrays of objects. Catalog version bumped. Andrew Dunstan, with some documentation assistance from Mer...
bank=# select json_object_keys(jobdesc) from job where jobdesc->>'jobname' = 'linux_os_vmstat'; jobname schedule values objects json_populate_record(base anyelement, from_json json, [, use_json_as_text bool=false] 这个函数较复杂,作用是按照第一个参数定义的数据类型,把第二个参数的Json数...
Returns the array as JSON. A PostgreSQL multidimensional array becomes a JSON array of arrays. Line feeds will be added between dimension 1 elements if pretty_bool is true. Syntax: array_to_json(anyarray [, pretty_bool]) Return Type json Example Code: SELECT array_to_json('{{2,8},{79...
Table 9-43. AdditionaljsonbOperators Note:The||operator concatenates the elements at the top level of each of its operands. It does not operate recursively. For example, if both operands are objects with a common key field name, the value of the field in the result will just be the value...
在PostgreSQL中,可以使用JSON函数和操作符来解析JSON字段。以下是解析JSON字段的一些方法: 1. 使用箭头操作符(->):箭头操作符用于从JSON对象中获取指定键的值。例如,假设有...
{ "sql_json_object_not_found", ERRCODE_SQL_JSON_OBJECT_NOT_FOUND }, { "too_many_json_array_elements", ERRCODE_TOO_MANY_JSON_ARRAY_ELEMENTS }, { "too_many_json_object_members", ERRCODE_TOO_MANY_JSON_OBJECT_MEMBERS }, { "sql_json_scalar_required", ERRCODE_SQL_JSON_SCALAR_REQUIRED }...
高扩展性PostgreSQL支持多种数据类型(如JSON、XML、HSTORE)和扩展机制,允许用户创建自定义的数据类型、操作符和索引。其强大的扩展功能使得开发者可以根据特定需求扩展数据库功能。 丰富的功能PostgreSQL支持诸如事务处理、视图、触发器、外键等标准SQL功能,并且提供了先进的特性如表继承、规则系统、外部数据包装器(FDW)、...
objects.aggregate(boolor=BoolOr(Q(rank__gt=2))) {'boolor': False} JSONBAgg¶ class JSONBAgg(expressions, distinct=False, filter=None, ordering=(), **extra)¶ 将输入值以 JSON 数组形式返回。 distinct¶ New in Django 3.2. 一个可选的布尔参数,用于确定数组值是否会被去重。默认值为 ...
I hope this helps clear up any confusion you might have had about querying nested JSON objects in Postgres. If you want to learn more about these operators or if you want to see what else you can do,here is a link to the docsfor JSON functions in Postgres. ...