MySQL查询根据另一个字段中的布尔值仅获取单个字段
让我们首先创建一个表-
mysql> create table DemoTable ( EmployeeId int NOT NULL AUTO_INCREMENT PRIMARY KEY, EmployeeName varchar(40), isMarried boolean );
使用插入命令在表中插入一些记录-
mysql> insert into DemoTable(EmployeeName,isMarried) values('Chris',true);
mysql> insert into DemoTable(EmployeeName,isMarried) values('Robert',false);
mysql> insert into DemoTable(EmployeeName,isMarried) values('Mike',false);
mysql> insert into DemoTable(EmployeeName,isMarried) values('Bob',true);
mysql> insert into DemoTable(EmployeeName,isMarried) values('Tom',true);使用select语句显示表中的所有记录-
mysql> select *from DemoTable;
这将产生以下输出-
+------------+--------------+-----------+ | EmployeeId | EmployeeName | isMarried | +------------+--------------+-----------+ | 1 | Chris | 1 | | 2 | Robert | 0 | | 3 | Mike | 0 | | 4 | Bob | 1 | | 5 | Tom | 1 | +------------+--------------+-----------+ 5 rows in set (0.00 sec)
以下是根据另一个字段中的布尔值仅获取单个字段的查询-
mysql> select EmployeeName from DemoTable where isMarried=true;
这将产生以下输出-
+--------------+ | EmployeeName | +--------------+ | Chris | | Bob | | Tom | +--------------+ 3 rows in set (0.00 sec)