44 lines
1 KiB
Markdown
44 lines
1 KiB
Markdown
## 1. 创建表
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```sql
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create table ttt(
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no int primary key,
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name char(10) not null,
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depno int,
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indate date,
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sal numeric(8,2)
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);
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// numrtic(a,b): 数字类型，总位数为8，小数点后b位
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// char(a): 定长为a的字符串
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// varchar(a): 变长字符串，最大长度为a
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```
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## 2. 删除表
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```sql
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drop table ttt;
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drop table ttt if exists;
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```
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## 3. 插入
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```sql
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insert into ttt values(1,"ttt",1,"2023-05-28",12.33);
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insert into ttt(no,name,depno,indate,sal) values(1,"ttt",1,"2023-05-28",12.33);
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insert into ttt(no,name,depno) values(1,"ttt",1);
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```
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## 4. distinct去除重复
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```sql
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selet distinct depno from ttt;
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```
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## 5.查询多个值
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```sql
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select name from ttt where depno in (2,3,5);
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select name from ttt where depno not in (2,3,5);
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```
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## 6. between
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```sql
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select name from ttt where indate between '2022-01-22' and '2023-04-30';
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// 等价
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select name from ttt where indate>='2022-01-22' and indate<>='2023-04-30';
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select name from ttt where indate not between '2022-01-22' and '2023-04-30';
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```
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