PROSAGA码农传奇-SqlServer-在sql server中不接受EXISTS

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  <P>
    口渴，使用
     <code>
      IF
    </code>
     条件而不是
     <code>
      While
    </code>
     执行逻辑运算。此外，您的查询是错误的，我这样修改它;
  </p>
   <pre>
    <code>
      IF(EXISTS(SELECT COLUMN_NAME FROM ( SELECT SC.name as TABLE_SCHEMA,
                                                 t.name as TABLE_NAME,
                                                 ind.name as indexName,
                                                 ind.type_desc AS type_Index,
                                  SUBSTRING(( SELECT ', ' + AC.name
                           FROM DATA.sys.[tables] AS T
                           INNER JOIN DATA.sys.[indexes] I   ON T.[object_id] = I.[object_id]
                           INNER JOIN DATA.sys.[index_columns] IC ON I.[object_id] = IC.[object_id] AND I.[index_id] = IC.[index_id]
                           INNER JOIN DATA.sys.[all_columns] AC ON T.[object_id] = AC.[object_id] AND IC.[column_id] = AC.[column_id] 
                           WHERE ind.[object_id] = I.[object_id] AND ind.index_id = I.index_id AND IC.is_included_column = 0
                           ORDER BY IC.key_ordinal
                     FOR    XML PATH('')), 2, 8000) AS COLUMN_NAME
              FROM DATA.sys.indexes ind 
              INNER JOIN DATA.sys.index_columns ic ON  ind.object_id = ic.object_id and ind.index_id = ic.index_id 
              INNER JOIN DATA.sys.columns col ON ic.object_id = col.object_id and ic.column_id = col.column_id 
              INNER JOIN DATA.sys.tables t ON ind.object_id = t.object_id
              INNER JOIN DATA.sys.schemas SC ON t.schema_id =  SC.schema_id
              WHERE SC.name ='SSCI_SALR') as SubQ
              WHERE COLUMN_NAME IN ( SELECT COLUMN_NAME FROM INFORMATION_SCHEMA.COLUMNS
                            WHERE DATA_TYPE IN ('nchar', 'nvarchar')
                            and TABLE_SCHEMA IN ('SSCI_SALR', 'SYSTEM_SALR'))
GROUP BY COLUMN_NAME))
begin
   print 'ok'
end

</code>
  </pre>
</DIV>