Postgresql数据库中的json类型字段使用示例详解

CREATE TABLE "test" (  
    "id" int8 ,
    "info" json NOT NULL
);

INSERT INTO "test"("id", "info") VALUES (1, '{"showcolor":"#C1E498"}');
INSERT INTO "test"("id", "info") VALUES (2, '{"showcolor":"#C1E497"}');
INSERT INTO "test"("id", "info") VALUES (3, '{"showcolor":"#C1E496"}');

SELECT info -> 'showcolor' AS color FROM test;

SELECT info ->> 'showcolor' AS color FROM test;

SELECT
   info ->> 'showcolor' AS color
FROM
   test
WHERE
   info ->> 'showcolor' = '#C1E496'