0x1 创建表
创建一张志愿者的数据表,记录每批参加志愿活动的人员名单。其中人员信息保存在json字段中。
-- ----------------------------
-- Table structure for volunteer
-- ----------------------------
DROP TABLE IF EXISTS "public"."volunteer";
create sequence volunteer_id increment by 1 minvalue 1 no maxvalue start with 1;
CREATE TABLE "public"."volunteer" (
"id" serial NOT NULL,
"batch" varchar(255) COLLATE "default",
"persons" json
)
WITH (OIDS=FALSE);
-- ----------------------------
-- Alter Sequences Owned By
-- ----------------------------
ALTER TABLE "public"."volunteer" ALTER COLUMN id SET DEFAULT nextval('volunteer_id');
-- ----------------------------
-- Primary Key structure for table volunteer
-- ----------------------------
ALTER TABLE "public"."volunteer" ADD PRIMARY KEY ("id");
知识点: (1)postgresql中自增长的id创建。 (2)修改表字段语句。 (3)标准sql中table name ,column name双引号。
0x2 插入数据
INSERT INTO "public"."volunteer" ("batch","persons") VALUES('第一批名单','{
"code": 0,
"data": {
"users": [
{
"Age": 33,
"ID": 1,
"Url": "http://blog.golang.org/crankshaw@20170502235840",
"UserName": "Crankshaw@20170502235840"
},
{
"Age": 31,
"ID": 2,
"Url": "https://jack.github.io",
"UserName": "Jack"
},
{
"Age": 22,
"ID": 3,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 4,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 5,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 6,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 7,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 8,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 9,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 12,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 13,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 14,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 15,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 16,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 17,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 20,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 21,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 22,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 23,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 24,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 25,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 28,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 29,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 30,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 31,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 32,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 33,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 36,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 37,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 38,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 39,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 40,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 41,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 44,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 45,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 46,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 47,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 48,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 49,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 52,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 53,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 54,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 55,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 56,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 57,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 60,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 61,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 62,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 63,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 64,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 65,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 68,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 69,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 70,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 71,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 72,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 73,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 76,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 77,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 78,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 79,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 80,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 81,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 84,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 85,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 86,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 87,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 88,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 89,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 90,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 91,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 92,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 93,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 94,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 95,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
},
{
"Age": 22,
"ID": 98,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 22,
"ID": 99,
"Url": "http://blog.golang.org/cock",
"UserName": "Cock"
},
{
"Age": 21,
"ID": 100,
"Url": "http://blog.golang.org/hickinbottom",
"UserName": "Hickinbottom"
},
{
"Age": 22,
"ID": 101,
"Url": "http://blog.golang.org/willy",
"UserName": "Willy"
},
{
"Age": 25,
"ID": 102,
"Url": "http://blog.golang.org/nutter",
"UserName": "Nutter"
},
{
"Age": 33,
"ID": 103,
"Url": "http://blog.golang.org/Pigg",
"UserName": "Pigg"
}
]
},
"msg": "Success"
}
');
0x3 条件查询json内容
查询年龄大于等于25岁以上的志愿者
SELECT row_number() OVER () as num, obj->>'UserName' as userName,obj->'Age' as age
FROM "public"."volunteer" vol, json_array_elements(vol.persons->'data'->'users') obj
WHERE (obj->>'Age')::int >= 25;
知识点: (1)查询结果的的row number生成。 (2)获取json对象中的子对象。 (3)转换json对象属性的数据类型。
