SqlServer和Oracle中一些常用的sql语句2

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WITH Emp
AS
(
SELECT E.Dept_Id
, Count(*) Emp_Count
FROM Employees E
GROUP BY E.Dept_Id
)

SELECT D.Dept_Name
, E.Emp_Count
FROM Departments D , Emp E
WHERE D.Dept_Id = E.Dept_Id
ORDER BY Emp_Count DESC
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/************************************************************
打印99乘法表
************************************************************/
--把重复用到的SQL语句放在with as 里面，取一个别名可用做子查询部分，后面的查询就可以用它
WITH Tally(N) AS
(
SELECT 1 N
--FROM DUAL
UNION ALL
SELECT N + 1 N
FROM   Tally
WHERE  N < 9
)
SELECT CAST(B.N AS VARCHAR)
+ ' * '
+ CAST(A.N AS VARCHAR)
+ ' = '
+ CAST(A.N * B.N AS VARCHAR)
Result
FROM   Tally A
CROSS JOIN Tally B

--------------------------------------------------------------
--SQL SERVER
--用table2中的数据 更新存在于table1的数据
UPDATE table1
SET
table1.UserName = table2.UserName,
table1.Pwd = table2.Pwd
FROM table2
WHERE table1.id=table2.id

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--Oracle
UPDATE Emp_Bak E
SET (Salary , Dept_Id)=
(
SELECT A.Salary, A.Dept_Id
FROM Adjustment A
WHERE E.Emp_Id = A.Emp_Id
)
WHERE E.Emp_Id=
(
SELECT A.Emp_Id
FROM Adjustment A
WHERE E.Emp_Id =
A.Emp_Id
)

UPDATE
(
SELECT E.Salary , A.Salary New_Salary
, E.Dept_Id, A.Dept_Id
New_Dept_Id
FROM Emp_Bak E, Adjustment A
WHERE E.Emp_Id = A.Emp_Id
) --(INLINE-VIEW)
SET Salary = New_Salary
, Dept_Id = New_Dept_Id

---Oracle和SQLServer补齐字符串的方法
SELECT RIGHT(REPLICATE('0',10)+LTRIM(1234),10);  --SQLServer

SELECT LPAD(1234,10,'0') FROM DUAL;   --Oracle
--结果 0000001234

-----特殊字符 模糊搜索 % _相关处理
SELECT *
FROM
(
SELECT '5% Discount' VAL
--FROM DUAL
UNION ALL
SELECT '59_' VAL
--FROM DUAL
) D
WHERE VAL LIKE '5\%%' ESCAPE '\'

SELECT *
FROM
(
SELECT '5% Discount' VAL
--FROM DUAL
UNION ALL
SELECT '59_' VAL
--FROM DUAL
) D
WHERE VAL LIKE '%\_' ESCAPE '\'

--還有SQL SERVER特有的
SELECT *
FROM
(
SELECT '5% Discount' VAL
UNION ALL
SELECT '59_' VAL
) D
WHERE VAL LIKE '5[%]%'

--
SELECT *
FROM
(
SELECT '5% Discount' VAL
UNION ALL
SELECT '59_' VAL
) D
WHERE VAL LIKE '%[_]'

------------------------------------------
--正则表达式搜索
--145, ORACLE
SELECT Val
FROM
(
SELECT '123' Val
FROM DUAL
UNION ALL
SELECT '456' FROM DUAL
UNION ALL
SELECT 'ABC' FROM DUAL
UNION ALL
SELECT 'xyz' FROM DUAL
UNION ALL
SELECT '@789' FROM DUAL
UNION ALL
SELECT '789@' FROM DUAL
)
WHERE 1=1
AND REGEXP_LIKE(Val, '^[0-9]') --測試1
--AND REGEXP_LIKE( Val, '^[^0-9]')--測試2
--AND REGEXP_LIKE(Val, '^[A-Za-z]')--測試3

--145, SQL SERVER
SELECT Val
FROM
(
SELECT '123' Val
UNION ALL
SELECT '456'
UNION ALL
SELECT 'ABC'
UNION ALL
SELECT 'xyz'
UNION ALL
SELECT '@789'
UNION ALL
SELECT '789@'
) A
WHERE 1=1
AND Val LIKE '[0-9]%' --測試1, 數字(0-9)
--AND Val LIKE '[^0-9]%'--測試2, 非數字
--AND Val LIKE '[A-Z]%' --測試,3 英文(A-Z)

--------------中文Unicode区间----------------
---------------------------------------------
WITH Tally(N) AS
(
SELECT 19966 N
UNION ALL
SELECT N +1 N
FROM Tally
WHERE N<40892
)
SELECT N, NCHAR(N) Word
FROM Tally
OPTION (MAXRECURSION 32000)

------------------利用中文是两个字节的特性判断-------------------
--150, SQL SERVER
SELECT Word
, LEN(Word)
, DATALENGTH(Word)
, CASE WHEN LEN(Word) = DATALENGTH(Word)  THEN '英文'
ELSE '中文'
END Judge
FROM
(
SELECT 'English' Word
--FROM DUAL
UNION ALL
SELECT '中文'
--FROM DUAL
UNION ALL
SELECT '堃'
--FROM DUAL
)  A

--149, ORACLE  利用中文是两个字节的特性判断
SELECT Word
, LENGTH(Word)  "Len"
, LENGTHB(Word) "LenB"
, CASE WHEN LENGTH(Word) = LENGTHB(Word)  THEN '英文'
ELSE '中文'
END Judge
FROM
(
SELECT 'English' Word
FROM DUAL
UNION ALL
SELECT '中文'
FROM DUAL
UNION ALL
SELECT '堃'
FROM DUAL
)