使用算數運算符-
, 查詢最低借閱量與最高借閱量的差值mysql
select max(borrowsum)-min(borrowsum) as 差值 from book;
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使用比較運算符(>
)查詢book表中借閱量大於10的書籍信息sql
select * from book where borrowsum > 10;
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使用right()
函數返回從字符串loveMySQL
右邊開始的5個字符函數
select right('ILoveMySQL',5);
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查詢數據表bookborrow中2011年的借閱信息post
-- 第1種方法
SELECT
*
FROM
bookborrow
WHERE
( DATEDIFF( borrowtime, '2011-01-01' ) > 0 AND DATEDIFF( borrowtime, '2011-01-01' ) < 365 )
OR
( DATEDIFF( returntime, '2011-01-01' ) > 0 AND DATEDIFF( returntime, '2011-01-01' ) < 365 );
-- 第2種方法
SELECT
*
FROM
bookborrow
WHERE
( borrowtime >= '2011-01-01' AND borrowtime <= '2011-12-31' )
OR
( returntime >= '2011-01-01' AND returntime <= '2011-12-31' );
-- 第3種方法
SELECT
*
FROM
bookborrow
WHERE
( borrowtime BETWEEN '2011-01-01' AND '2011-12-31' )
OR
( returntime BETWEEN '2011-01-01' AND '2011-12-31' );
-- 第4種方法
SELECT
*
FROM
bookborrow
WHERE
borrowtime LIKE '2011%'
OR
returntime LIKE '2011%';
-- 第5種方法
SELECT
*
FROM
bookborrow
WHERE
borrowtime REGEXP '^2011'
OR
returntime REGEXP '^2011';
-- 第6種方法
SELECT
*
FROM
bookborrow
WHERE
YEAR ( borrowtime ) = '2011'
OR
YEAR ( returntime ) = '2011';
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使用concat()
函數鏈接兩個字符串spa
select concat('ILove','MySQL');
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查詢選修了C1或C2且分數大於或等於85分的學生學號code
SELECT
student.sid
FROM
student,
scourse
WHERE
student.sid = scourse.sid
AND scourse.cid IN ( 'C1', 'C2' )
AND score >= 85;
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查詢工資不在1500~2000之間的教師號,姓名,職稱ci
SELECT
tname,
tid,
title
FROM
teacher
WHERE
salary NOT BETWEEN 1500
AND 2000;
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從bookinfo中查詢書的名稱和單價, 使書的單價精確到個位便可字符串
select bname,TRUNCATE(bprice,1) from bookinfo;
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從bookinfo表中查詢全部的書名, 數量以及單價信息, 並要求全部書名用大寫字母表示get
SELECT
upper( bname ),
quantity,
bprice
FROM
bookinfo;
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從bookinfo表中查詢全部以processing
結尾的書名, 數量, 單價信息it
SELECT
bname,
quantity,
bprice
FROM
bookinfo
WHERE
bname LIKE '%processing';
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SELECT
bname,
quantity,
bprice
FROM
bookinfo
WHERE
RIGHT ( bname, 10 ) = 'processing';
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SELECT
bname,
quantity,
bprice
FROM
bookinfo
WHERE
bname REGEXP 'processing$' = 1;
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從bookinfo
表中查詢全部的書名, 單價信息以及將書名中的字符串processing
替換爲pro.
後的結果
SELECT
bname,
REPLACE ( lower( bname ), 'processing', 'pro.' ) AS 轉換後,
bprice
FROM
bookinfo;
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