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常用增删改查sql示例

一、插入資料

    (1)INSERT INTO Persons VALUES ('Gates', 'Bill', 'Xuanwumen 10', 'Beijing')

    (2)INSERT INTO Persons (LastName, Address) 

           VALUES ('Wilson', 'Champs-Elysees'),('Wilson2', 'Champs-Elysees2')

    (3)INSERT INTO Persons select * from Persons2

    (4)SELECT LastName,FirstName INTO Persons_backup FROM Persons

二、删除資料

    (1)DELETE FROM Person WHERE LastName = 'Wilson'

    (2)drop Person

三、修改資料

    (1)UPDATE Person SET Address = 'Zhongshan 23', City = 'Nanjing' 

            WHERE LastName = 'Wilson'

    (2)update p set p.Address = 'Zhongshan 23'

    from Person p inner join City c on p.cityId = c.id where c.name = '北京'

四、查詢語句

1、普通查詢:

    (1)SELECT LastName,FirstName FROM Persons WHERE City='Beijing' 

            ORDER BY Company DESC, OrderNumber ASC

    (2)SELECT DISTINCT Company FROM Orders 

    (3)SELECT * FROM Persons WHERE (FirstName='Thomas' OR FirstName='William') 

                AND  LastName='Carter'

    (4)SELECT * FROM Persons WHERE LastName IN ('Adams','Carter')

    (5)SELECT * FROM Persons WHERE LastName NOT BETWEEN 'Adams' AND 'Carter'

    (6)SELECT TOP 2 * FROM Persons (隻sqlserver)

    (7)SELECT * FROM Persons LIMIT 5 (隻mysql)

    (8)SELECT po.OrderID, p.LastName, p.FirstName FROM Persons AS p, 

            Product_Orders AS po WHERE p.LastName='Adams' AND p.FirstName='John'(别名)

    (9)SELECT column_name(s) FROM table_name1 UNION ALL SELECT column_name(s)                     FROM table_name2(合并結果集,union all是直接連接配接,取到得是所有值,

                記錄可能有重複;union 是取唯一值,記錄沒有重複)

2、like查詢

    (1)SELECT * FROM Persons WHERE City LIKE '%' + 'N' + '%'

    (2)SELECT * FROM Persons WHERE City LIKE 'N%'(這種方式可能用到索引)

    (3)SELECT * FROM user where userName like '發_1_2'(_僅替代一個字元)

    (4)SELECT top 10 * FROM user where userId like '[23]%'

            ([charlist]字元列中的任何單一字元,隻sqlserver有用)

    (5)SELECT top 10 * FROM user where userId like '[^23]0%'

            ([^charlist]不在字元列中的任何單一字元,隻sqlserver有用)

3、關聯查詢

    SELECT Persons.LastName, Persons.FirstName, Orders.OrderNo FROM Persons

        INNER JOIN Orders ON Persons.Id_P = Orders.Id_P ORDER BY Persons.LastName

    (1)JOIN: 如果表中有至少一個比對,則傳回行

    (2)LEFT JOIN: 即使右表中沒有比對,也從左表傳回所有的行

    (3)RIGHT JOIN: 即使左表中沒有比對,也從右表傳回所有的行

    (4)FULL JOIN: 隻要其中一個表中存在比對,就傳回行

4、分頁查詢

    (1)SELECT * FROM ceshi limit 0,10(隻mysql,從第1個資料開始,取10條資料)

    (2)select top 10 o.* from (select row_number() over(order by userId)as rowNumber,* from             user) as o where rowNumber>0(隻sqlserver,從第1個資料開始,取10條資料)

    (3)SELECT * FROM user order by userId  OFFSET 0 ROW FETCH NEXT 10 ROWS ONLY

        (隻sqlserver,新版的sqlserver可用,比上一種高效)

四、java寫資料庫語句需要特别注意的問題

1、SqlServer 對語句的條數和參數的數量都有限制,分别是 1000 和 2100;

2、Mysql 對語句的長度有限制,預設是 4M;

3、where條件中,=與!=兩邊都不能有null值,否則判斷會出錯。需要對有null值的字段作比較時,       sqlserver需要用isnull(null,'default_value')把null值轉化為預設值再比較;mysql需要用ifnull(null,'default_value')把null值轉化為預設值再比較。    

 本文轉自 獨孤環宇 51CTO部落格,原文連結:http://blog.51cto.com/snowtiger/1928756