Warning: mysqli_query(): (HY000/1030): Got error -1 from storage engine in /www/wwwroot/shulanxt/wp-includes/wp-db.php on line 2007
SQL SELECT语句_SQL SELECT_SQL 查询 - 树懒学堂
  • 导航

SQL SELECT语句


SQL SELECT语句

SELECT 语句用于从数据库中选取数据。结果被存储在一个结果表中,称为结果集。

SQL SELECT 语法

SELECT column_name FROM table_name;

例如:

SELECT * FROM Users;

注:”*”表示显示Users表中所有的列

演示数据库

下面是选自”Websites”表中的数据:

id name url alexa country
1 google www.google.com 1 US
2 百度 www.baidu.com 6 CN
3 树懒学堂 www.shulanxt.com 58851 CN
4 yahoo www.yahoo.com 82 US
5 淘宝 www.taobao.com 18 CN

SELECT Column 实例

下面的 SQL 语句从 “Websites” 表中选取 “name” 和 “country” 列:

SELECT name,country FROM Websites;


Warning: mysqli_query(): (HY000/1030): Got error -1 from storage engine in /www/wwwroot/shulanxt/wp-includes/wp-db.php on line 2007
  SQL 语法
Warning: mysqli_query(): (HY000/1030): Got error -1 from storage engine in /www/wwwroot/shulanxt/wp-includes/wp-db.php on line 2007
SQL SELECT DISTINCT 语句