JOIN
语句来连接多个表并检索相关数据。JOIN
语句来连接多个表并检索相关数据。DISTINCT
关键字。,,``sql,SELECT DISTINCT column1, column2,FROM table1,JOIN table2 ON table1.id = table2.id;,
``,,这样可以确保结果集中没有重复的行。sql,SELECT a.column1, b.column2,FROM table1 a,JOIN table2 b ON a.id = b.id;,
``JOIN
子句来实现。常见的联表类型包括内连接(INNER JOIN)、左连接(LEFT JOIN)、右连接(RIGHT JOIN)和全连接(FULL JOIN)。通过这些操作,可以从多个表中获取相关数据。,,``sql,SELECT a.column1, b.column2,FROM table1 a,INNER JOIN table2 b ON a.id = b.id;,
`,,这个查询将返回
table1 和
table2` 中匹配的记录。Powered By Z-BlogPHP 1.7.3
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