postgresql查询集合结果⽤逗号分隔返回字符串处理的操作关键字:
string_agg('' , '')
例如:
select string_agg(name||'' , ',') from sys_user
补充:PostgreSQL 字段⽤逗号 “,”隔开判断是否含有某个值
Array Functions and Operators
-- ----------------------------
-- Table structure for T_STUDENT
-- ----------------------------
DROP TABLE IF EXISTS "public"."T_STUDENT";
CREATE TABLE "public"."T_STUDENT" (
"id" int4,
"name" varchar(255) COLLATE "default",
"course" varchar(255) COLLATE "default"
字符串截取逗号前面的)
WITH (OIDS=FALSE)
;
-- ----------------------------
-
- Records of T_STUDENT
-- ----------------------------
INSERT INTO "public"."T_STUDENT" VALUES ('1', '李四', '12,45,1,66,7,89');
INSERT INTO "public"."T_STUDENT" VALUES ('2', '刘⼀', '1,5,8,9');
INSERT INTO "public"."T_STUDENT" VALUES ('3', '王五', '0,4,2');
INSERT INTO "public"."T_STUDENT" VALUES ('4', '张三', '1,2,5,7');
-- ----------------------------
-- Alter Sequences Owned By
-- ----------------------------
-- ----------------------------
-- Table structure for T_STUDENT
-
- ----------------------------
DROP TABLE IF EXISTS "public"."T_STUDENT";
CREATE TABLE "public"."T_STUDENT" (
"id" int4,
"name" varchar(255) COLLATE "default",
"course" varchar(255) COLLATE "default"
)
WITH (OIDS=FALSE)
;
-- ----------------------------
-- Records of T_STUDENT
-
- ----------------------------
INSERT INTO "public"."T_STUDENT" VALUES ('1', '李四', '12,45,1,66,7,89');
INSERT INTO "public"."T_STUDENT" VALUES ('2', '刘⼀', '1,5,8,9');
INSERT INTO "public"."T_STUDENT" VALUES ('3', '王五', '0,4,2');
INSERT INTO "public"."T_STUDENT" VALUES ('4', '张三', '1,2,5,7');
-- ----------------------------
-- Alter Sequences Owned By
-- ----------------------------
id name course
4 张三 1,2,5,7
1 李四 12,45,1,5,66,7,89
2 刘⼀ 1,5,8,9
3 王五 0,4,2
SELECT * FROM "public"."T_STUDENT" WHERE string_to_array(course, ',') @> ARRAY['2','7']
结果:
id name course
4 张三 1,2,5,7
SELECT * FROM "public"."T_STUDENT" WHERE string_to_array(course, ',') <@ array['5','12','45','1','0','4','2']
结果:
id name course
3 王五 0,4,2
SELECT * FROM "public"."T_STUDENT" WHERE string_to_array(course, ',') && ARRAY['5','8','225','111']
结果:
id name course
4 张三 1,2,5,7
2 刘⼀ 1,5,8,9
以上为个⼈经验,希望能给⼤家⼀个参考,也希望⼤家多多⽀持。如有错误或未考虑完全的地⽅,望不吝赐教。
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