json - 从 postgreSQL 中的表中查询 json 对象

Question

我想在 postgreSql 中对表中的 json 对象使用 where 条件。例如，我需要如何执行此操作：我有一个表“测试”，它具有三列名称（varchar），url（varchar），more（json）。我需要检索 css21Colors = Purple 的日期。more 是 json 类型，下面是 more 字段的值。

请让我知道查询相同的语法应该是什么？

more = {"colorTree":{"Purple":[{"Spanish Violet":"#522173"}],
"Brown":[{"Dark Puce":"#4e3347"}],"White":[{"White":"#ffffff"}],
"Black":[{"Eerie Black":"#1d0d27"}],"Gray":[{"Rose Quartz":"#a091a4"}]},
"sizeoutscount":0,"css21Colors":{"Purple":69,"Brown":5,"White":4,"Black":17,"Gray":3},
"sizeins": [],"sizeinscount":0,"sizeouts":[],"allsizes":["8","10","16"],
"css3Colors": {"Rose Quartz":3,"White":4,"Dark Puce":5,"Eerie Black":17,"Spanish
Violet":69},"hexColors":{"#522173":69,"#4e3347":5,"#ffffff":4,"#1d0d27":17,"#a091a4":3}}

Answer 1

SELECT more->'css21Colors'->'Purple' FROM test;

此外，您只能查询包含该键的行。

SELECT
  more->'css21Colors'->'Purple'
FROM
  test
WHERE
  (more->'css21Colors')::jsonb ? 'Purple';

介意切换到jsonb数据类型。