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MSSQL基本語法及範例操作語句

2022-04-11 13:02:41

重新整理本地快取

Ctrl+Shift+R

查詢

select *from [table]

修改

1、普通更新

UPDATE [table] set [欄位]=[values]

2、關聯表更新

UPDATE A SET A1 = B1, A2 = B2, A3 = B3 FROM A, B WHERE A.ID = B.ID

刪除(資料)

delete [table]

刪除(表)

drop [table]

條件查詢

select *from [table] where [欄位]=[values]

事務

1 開始事務: begin transaction

2 提交事務:commit transaction

3 回滾事務: rollback transaction

4 結束事務: 提交或回滾事務都將結束事務

/*--開始事務--*/
begin transaction
declare @errorSum int    --定義變數,用於累計事務執行過程中的錯誤
/*--轉帳--*/
update bank set currentMoney=currentMoney-800 where customerName='張三'
set @errorSum=@errorSum+@@error    --累計是否有錯誤
update bank set currentMoney=currentMoney+800 where customerName='李四'
set @errorSum=@errorSum+@@error --累計是否有錯誤

print '檢視轉帳事務過程中的餘額'
select * from bank

/*--根據是否有錯誤,確定事務是提交還是回滾--*/
if @errorSum>0
    begin
        print '交易失敗,回滾事務.'
        rollback transaction
    end
else
    begin
        print '交易成功,提交事務,寫入硬碟,永久儲存!'
        /*--提交併且結束事務--*/
        commit transaction
    end
go

print '檢視轉帳後的餘額'
select * from bank
go

查詢所有表名

select * from sys.tables

查詢所有表包含的欄位名

select * from sys.columns

查詢所有欄位說明

select * from sys.extended_properties

根據表查詢所含欄位說明

SELECT t.[name] AS 表名,c.[name] AS 欄位名,cast(ep.[value]
as varchar(100)) AS [欄位說明]
FROM sys.tables AS t
INNER JOIN sys.columns AS c 
ON t.object_id = c.object_id
LEFT JOIN sys.extended_properties AS ep
ON ep.major_id = c.object_id AND ep.minor_id = c.column_id WHERE ep.class =1
AND t.name='UTB_GBNT_PROJ_INFO'--------表名

建立檢視

create view ViewName
(欄位1,欄位2)
as
(
    select 欄位1, 欄位2 
    from [table] 
)

資料字典

SELECT t.FieldExp 名稱,t.ColumnName 程式碼,

case t.FieldDataType 
when 'bigint' then t.FieldDataType
when 'int' then t.FieldDataType
when 'datetime' then t.FieldDataType
when 'numeric' then t.FieldDataType
when 'nvarchar' then (cast(t.FieldDataType as varchar(100))+'('+cast(t.Fieldlength as varchar(100))+')')
when 'decimal' then (cast(t.FieldDataType as varchar(100))+'('+cast(t.Fieldlength as varchar(100))+','+cast(t.Scale as varchar(100))+')')
end as 資料型別

,t.Fieldlength 長度,t.Scale 精確度

,case t.FieldNullable
when 0 then '不為空'
when 1 then '' end as 說明

from (select 
colorder=C.column_id, 
FieldExp=ISNULL(PFD.[value],N''), 
ColumnName=C.name, 
FieldDataType=T.name, 
Fieldlength=COLUMNPROPERTY(c.object_id ,c.name ,'PRECISION'), 
Scale=C.scale,
FieldNullable=C.is_nullable
--FieldDefVal=D.definition
FROM sys.columns C 
INNER JOIN sys.objects O 
ON C.[object_id]=O.[object_id] 
AND (O.type='U' or O.type='V') 
AND O.is_ms_shipped=0 
INNER JOIN sys.types T 
ON C.user_type_id=T.user_type_id 
LEFT JOIN sys.default_constraints D 
ON C.[object_id]=D.parent_object_id 
AND C.column_id=D.parent_column_id 
AND C.default_object_id=D.[object_id] 
LEFT JOIN sys.extended_properties PFD 
ON PFD.class=1 
AND C.[object_id]=PFD.major_id 
AND C.column_id=PFD.minor_id 
LEFT JOIN sys.extended_properties PTB 
ON PTB.class=1 
AND PTB.minor_id=0 
AND C.[object_id]=PTB.major_id 
LEFT JOIN 
( 
SELECT 
IDXC.[object_id], 
IDXC.column_id, 
Sort=CASE INDEXKEY_PROPERTY(IDXC.[object_id],IDXC.index_id,IDXC.index_column_id,'IsDescending')
WHEN 1 THEN 'DESC' WHEN 0 THEN 'ASC' ELSE '' END,  
PrimaryKey=CASE WHEN IDX.is_primary_key=1 THEN N'√'ELSE N'' END, 
IndexName=IDX.Name  
FROM sys.indexes IDX  
INNER JOIN sys.index_columns IDXC  
ON IDX.[object_id]=IDXC.[object_id]  
AND IDX.index_id=IDXC.index_id  
LEFT JOIN sys.key_constraints KC  
ON IDX.[object_id]=KC.[parent_object_id]  
AND IDX.index_id=KC.unique_index_id  
INNER JOIN  
(  
SELECT [object_id], Column_id, index_id=MIN(index_id)  
FROM sys.index_columns  
GROUP BY [object_id], Column_id  
) IDXCUQ  
ON IDXC.[object_id]=IDXCUQ.[object_id]  
AND IDXC.Column_id=IDXCUQ.Column_id  
AND IDXC.index_id=IDXCUQ.index_id  
) IDX  
ON C.[object_id]=IDX.[object_id]  
AND C.column_id=IDX.column_id  
WHERE O.name='--tablename--')as t  ORDER BY colorder,ColumnName
SELECT  
表名=case when a.colorder=1 then d.name else '' end, 
表說明=case when a.colorder=1 then isnull(f.value,'') else '' end,
欄位序號=a.colorder, 
欄位名=a.name, 
標識=case when COLUMNPROPERTY(a.id,a.name,'IsIdentity')=1 then '√'else '' end, 
主鍵=case when exists(SELECT 1 FROM sysobjects where xtype='PK' and name in (
  SELECT name FROM sysindexes WHERE indid in(
   SELECT indid FROM sysindexkeys WHERE id = a.id AND colid=a.colid 
   ))) then '√' else '' end, 
型別=b.name, 
佔用位元組數=a.length, 
長度=COLUMNPROPERTY(a.id,a.name,'PRECISION'), 
小數位數=isnull(COLUMNPROPERTY(a.id,a.name,'Scale'),0), 
允許空=case when a.isnullable=1 then '√'else '' end, 
預設值=isnull(e.text,''), 
欄位說明=isnull(g.[value],'') 
FROM syscolumns a 
left join systypes b on a.xtype=b.xusertype 
inner join sysobjects d on a.id=d.id and d.xtype='U' and d.name<>'dtproperties' 
left join syscomments e on a.cdefault=e.id 
left join sys.extended_properties g on a.id=g.major_id and a.colid=g.minor_id 
left join sys.extended_properties f on d.id=f.major_id and f.minor_id =0 
--where d.name='要查詢的表' --如果只查詢指定表,加上此條件   
order by a.id,a.colorder

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