30 lines
653 B
Markdown
30 lines
653 B
Markdown
关于 DELETE 语句
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DELETE 语句用来删除表中的记录。
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简单的 DELETE 语句格式如下：
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```javascript
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DELETE FROM table_name [ WHERE condition ] ;
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```
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其中，WHERE 条件子句是可选的，如果没有提供就全表删除。如果表记录数多达几百万以上，会形成大事务，可能会有性能问题。建议带上 WHERE 条件分批删除；或者使用 TRUNCATE TABLE 语句。
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示例：删除表中数据
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```javascript
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delete from ordr where o_w_id=2;
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delete from ordr ;
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```
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除了 DELETE 语句外，REPLACE INTO 语句也可能会删除数据。
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