CREATE TABLE students
(
 id integer NOT NULL,
 name character varying(255),
 sex character varying(255),
 class character varying(255),
 "like" character varying(255),
 school character varying(255),
 phone character varying(255)
)

INSERT INTO "public"."students" ("id", "name", "sex", "class", "like", "school", "phone") 
VALUES ('1', '大猫', '女', '一年级', '绘画', '第三小学', '2345');
INSERT INTO "public"."students" ("id", "name", "sex", "class", "like", "school", "phone") 
VALUES ('2', '小厌', '男', '三年级', '书法', '第四小学', '2346');
INSERT INTO "public"."students" ("id", "name", "sex", "class", "like", "school", "phone") 
VALUES ('3', '库库', '女', '二年级', '绘画', '第三小学', '2342');
INSERT INTO "public"."students" ("id", "name", "sex", "class", "like", "school", "phone") 
VALUES ('4', '艾琳', '女', '四年级', '书法，钢琴', '第四小学', '2349');

select * from students

replace(string text, from text, to text)

select replace('一条黑色的狗','黑','黑白相间')

update students set name=replace(name,'大猫','小猫咪的姐姐')

select * from students where school='第四小学' ORDER BY replace(name,'艾琳','1')

translate(string text, from text, to text)

select translate('她真是好看', '好看','漂亮')

select * from students where phone like '2%' 
ORDER BY translate(class, '一二三四','1234')

select * from students where phone like '2%' 
ORDER BY translate(name, '库小厌猫咪艾','1234')

select position('.' in '1.1.2.10');
select split_part('1.1.2.10','.',length('1.1.2.10') - length(translate('1.1.2.10','.',''))+1);
select split_part('1.1.2','.',length('1.1.2') - length(translate('1.1.2','.',''))+1);
select length(translate('1.1.2.10','.','a'))+1 as num
select translate('1.1.2.10','.','')
select strpos('1.1.2.10','.')
select instr('1.1.2.10','.',1,3) 
select length('1.1.2.10') - length(translate('1.1.2.10','.',''))