where in 用法，请问

select * from feelist where feebuyerSp in("+feebuySp+") and feebuyerSp is not null
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string sql = "";
if(feebuySp == "")
{
  sql = select * from feelist }
else
{
  sql = select * from feelist where feebuyerSp in("+feebuySp+")
}

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SQL code
select * from feelist where feebuyerSp is null or feebuyerSp ='' or feebuyerSp  like '%'+feebuySp+'%')
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SQL code
if isnull(feebuySp,'')=''select * from feelist
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SQL code
select * from feelist where feebuyerSp in("+feebuySp+") or feebuyerSp !=""
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SQL code
string sql = "select * from feelist";if(feebuyerbhFX.Text.Trim().Length){  string feebuySp="'"+feebuyerbhFX.Text.Replace(",","','")+"'";   sql += " where feebuyerSp in("+feebuySp+")";}
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如果feebuySp<>null then  
select * from feelist where feebuyerSp in("+feebuySp+")
否则 select * from feelist
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引用楼主 liuvb 的帖子:

如果feebuySp不为空时，这样没问题，如果feebuySp为空时，我想得到全部记录，应该怎么改一下？ 
string feebuySp="'"+feebuyerbhFX.Text.Replace(",","','")+"'"; 

select * from feelist where feebuyerSp in("+feebuySp+")

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C# code
 string feebuySp = "'" + feebuyerbhFX.Text.Replace(",", "','") + "'";        string sql = "select * from feelist where feebuyerSp in ('"+feebuySp+"')";
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SQL code
select * from feelist where feebuyerSp is null
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在程序中加个判断，分别用不同的SQL
if(feebuySp==null)
{
  select * from feelist
}
else
{
  select * from feelist where feebuyerSp in("+feebuySp+")
}
------解决方案--------------------
引用楼主 liuvb 的帖子:

如果feebuySp不为空时，这样没问题，如果feebuySp为空时，我想得到全部记录，应该怎么改一下？ 
string feebuySp="'"+feebuyerbhFX.Text.Replace(",","','")+"'"; 

select * from feelist where feebuyerSp in("+feebuySp+")

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引用楼主 liuvb 的帖子:
SQL codeselect * from feelist where feebuyerSp is null or feebuyerSp in("+feebuySp+")

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