1.聲明變量
DECLARE @F001 SMALLINT,
@F002 INTEGER,
@F003 VARCHAR(20),
@F004 CHAR(20),
@F002 MONEY
2.賦值語句
set @F001 = space(40)
3.條件判斷(IF...ELSE)
If condition Begin
[ statements ]
END
ELSE BEGIN
[ elseifstatements ]
END
4.多分支判斷(case...when...then...else...end)
SET @F011 =
CASE
WHEN [testexpression1] THEN @F001
WHEN [testexpression2] THEN @F002
WHEN [testexpression3] THEN @F003
WHEN [testexpression4] THEN @F004
END
5.循環(while)
While condition Begin
[ statements ]
End
6.動態定義游標
SET @strSQL = ' DECLARE name_cursor CURSOR FOR ' + @inSQL
EXEC (@strSQL)
7.遍歷游標
FETCH NEXT FROM name_cursor into @F001,@F002
WHILE @@FETCH_STATUS = 0 BEGIN
FETCH NEXT FROM name_cursor into @F001,@F002
END
說明:FETCH_STATUS檢索到數據返回0,失敗返回-1,可判斷是否滾動未到結尾。
8.獲得游標行數
SET @RECCNT = @@ROWCOUNT
9.事務處理
BEGIN distributed transaction
WHILE @@TRANCOUNT > 0
commit transaction
10.字符串連接
SET @m_sql = @m_sql + ' Where F001 = ''' + @F001 + ''''
SET @m_sql = @m_sql + ' F002 = ' + CONVERT(varchar,@F002)
11.創建臨時表存儲外部數據表
說明:臨時過程用 # 和 ## 命名,可以由任何用戶創建。創建過程后,局部過程的所有者是唯一可以使用該過程的用戶。
CREATE TABLE #DMPARHED
(FMCD int,
FMNAM varchar(50),
MGYO1 smallint,
constraint DMPARHED_P primary key (FMCD))
SET @aSQL = ''
SET @aSQL = @aSQL + 'INSERT INTO #DMPARHED'
SET @aSQL = @aSQL + ' SELECT FMCD,FMNAM,MGYO1 FROM'
SET @aSQL = @aSQL + ' OPENQUERY(Lk_MDB_NEO32, ''SELECT FMCD,FMNAM,MGYO1 FROM DMPARHED'
SET @aSQL = @aSQL + ' WHERE SYSNO = 1'')'
execute(@aSQL)
創建臨時表的另類方法:
select a.name,a.password from
with
as temp1
select * from emp
(select * from temp1
union
select * from temp1) a
where a.name='hao';
12.存儲過程的調用及返回值
(1)存儲過程的聲明
CREATE PROCEDURE name_produce
@F001 VARCHAR(20),
@F002 SMALLINT OUTPUT
(2)VB.NET調用存儲過程
Private SqlCmd As New OleDb.OleDbCommand
SqlCmd.CommandText = "prNK3020SC03"
SqlCmd.CommandType = CommandType.StoredProcedure
Dim parampre1 As OleDb.OleDbParameter = SqlCmd.Parameters.Add( _
New OleDb.OleDbParameter("@F001", OleDb.OleDbType.VarChar, 20, _
ParameterDirection.Input))
Dim parampre2 As OleDb.OleDbParameter = SqlCmd.Parameters.Add( _
New OleDb.OleDbParameter("@F002", OleDb.OleDbType.SmallInt))
parampre2.Direction = ParameterDirection.Output
SqlCmd.Parameters("@F001").Value = aF001
SqlCmd.Parameters("@F002").Value = aF002
SqlCmd.ExecuteNonQuery()
aF002 = SqlCmd.Parameters("@F002").Value.ToString()
(3)存儲過程調用存儲過程
DECLARE @C001 VARCHAR(20),
@C002 SMALLINT
EXEC name_produce @C001,@C002 output
CREATE PROCEDURE dbo.getUserName
@UserID int,
@UserName varchar(40) output
as
set nocount on
begin
if @UserID is null return
select @UserName=username
from dbo.[userinfo]
where userid=@UserID
return
end
13.Update語句常見錯誤總結
--√
Update name_table set
F001 = @F181,
F002 = @F182
Where
F003 = @F003
--×
Update name_table
F001 = @F181,
F002 = @F182
Where
F003 = @F003
--×
Update name_table set
F001 = @F181,
F002 = @F182,
Where
F003 = @F003
--×
Update name_table set
,F001 = @F181
,F002 = @F182
Where
F003 = @F003
14.Insert語句常見語法錯誤總結
--√
INSERT INTO name_table(
,KEY_FIELD,BUSYOCD
)Values(
@F001,@F002
)
--×
INSERT INTO name_table(
F001,F002
)Values(
,@F001,@F002
)
--×
INSERT INTO name_table(
F001,F002
)Values(
@F001,@F002,
)
--×
INSERT name_table(
F001,F002
)Values(
@F001,@F002
)