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MySQL筆記之基本查詢(xún)的應(yīng)用詳解_MySQL教程

編輯Tag賺U幣

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參考表：student



多字段查詢(xún)

復(fù)制代碼 代碼如下:hl5o.cn

mysql> select id,name,birth from student;


所有字段查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student;


where指定查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where id=901;
mysql> select * from student where id>=904;
mysql> select name from student where department='計(jì)算機(jī)系';


in指定集合查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where birth in(1988,1990);
mysql> select * from student where id in(903,906);

not in非范圍查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where birth not in(1990,1998);


between and指定范圍查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where birth between 1986 and 1988;


not between and不在指定范圍的查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where id not between 904 and 906;


like字符串匹配查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where name like '_三';
mysql> select * from student where name like '張三';
mysql> select * from student where name like '張%';


not like不匹配查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where name not like '張%';


null查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where address is null;


and多條件查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where name like '張%' and birth>1985;
mysql> select * from student where name like '張%' and birth>1985 and id like '%3';


or多條件查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where id=905 or birth=1988;
mysql> select * from student where id=905 or birth=1988 or sex='女';

 

distinct查詢(xún)結(jié)果不重復(fù)

復(fù)制代碼 代碼如下:hl5o.cn

mysql> select distinct sex from student;
mysql> select distinct department from student;


order by查詢(xún)結(jié)果排序
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student order by birth;
mysql> select * from student order by birth asc;
mysql> select * from student order by birth desc;


group by分組查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select sex,group_concat(name) from student group by sex;
mysql> select sex,count(name) from student group by sex;


正則表達(dá)式查詢(xún)
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student where birth regexp '1988|1990';


limit限制查詢(xún)結(jié)果數(shù)量
復(fù)制代碼 代碼如下:hl5o.cn

mysql> select * from student limit 2;
mysql> select * from student limit 1,3;

 


分享：MySQL筆記之索引的使用
索引是創(chuàng)建在表上的，對(duì)數(shù)據(jù)庫(kù)表中一列或多列的值進(jìn)行排序的一種結(jié)構(gòu)其作用主要在于提高查詢(xún)的速度，降低數(shù)據(jù)庫(kù)系統(tǒng)的性能開(kāi)銷(xiāo)

來(lái)源：模板無(wú)憂(yōu)//所屬分類(lèi)：MySQL教程/更新時(shí)間：2013-05-04
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