这里对非ntext,nvarchar,image字段有效,这些字段要别外处理.这下面的内容,部分我是自己用过的.对于ntext等字段大于8000的我没有试过.一起写在这里
代码如下:declare @t varchar(255),@c varchar(255)
declare table_cursor cursor for select a.name,b.name
from sysobjects a,syscolumns b ,systypes c
where a.id=b.id and a.xtype='u' and c.name
in ('char', 'nchar', 'nvarchar', 'varchar','text','ntext'/* --这里如果你的text(ntext)类型没有超过8000(4000)长度,才可以使用*/)
declare @str varchar(500),@str2 varchar(500)
set @str='a' /*这里是你要替换的字符*/
set @str2='' /*替换后的字符*/
open table_cursor
fetch next from table_cursor
into @t,@c while(@@fetch_status=0)
begin exec('update [' + @t + '] set [' + @c + ']=replace(cast([' + @c + '] as varchar(8000)),'''+@str+''','''+ @str2 +''')')
fetch next from table_cursor
into @t,@c end close table_cursor deallocate table_cursor;
小于8000的处理
update buyok_Orderlist set Notes=replace(cast(Notes as varchar(8000)),'a','')
如果text/ntext超过8000/4000,看如下例子
declare @pos int
declare @len int
declare @str nvarchar(4000)
declare @des nvarchar(4000)
declare @count int
set @des ='
set @len=len(@des)
set @str= '
set @count=0--统计次数.
WHILE 1=1
BEGIN
select @pos=patINDEX('%'+@des+'%',propxmldata) - 1
from 表名
where 条件
IF @pos>=0
begin
DECLARE @ptrval binary(16)
SELECT @ptrval = TEXTPTR(字段名)
from 表名
where 条件
UPDATETEXT 表名.字段名 @ptrval @pos @len @str
set @count=@count+1
end
ELSE
break;
END
select @count

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The basic operations of MySQL include creating databases, tables, and using SQL to perform CRUD operations on data. 1. Create a database: CREATEDATABASEmy_first_db; 2. Create a table: CREATETABLEbooks(idINTAUTO_INCREMENTPRIMARYKEY, titleVARCHAR(100)NOTNULL, authorVARCHAR(100)NOTNULL, published_yearINT); 3. Insert data: INSERTINTObooks(title, author, published_year)VA


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