# **sql where 条件**
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where 条件用于过滤数据
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### **sql where 条件**
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where 条件被用来提取达到指定标准的数据
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### **sql where 语法**
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>SELECT column_name,column_name
FROM table_name
WHERE column_name operator value;
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### **where 条件案例**
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下面这条sql语句从“Customers”表中筛选出国家是 “Mexico”的所有数据
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>SELECT * FROM Customers
WHERE Country='Mexico';
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### **文本字段和 数字字段**
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SQL需要单引号的文本值（大多数数据库系统也将允许双引号）
但是，数字字段不应包含在引号中：
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>SELECT * FROM Customers
WHERE CustomerID=1;
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