Question

我在循环中运行以下一批语句，直到受影响的行数返回为0：

DECLARE @ScopeTable TABLE (  KeyField bigint,  PRIMARY KEY ( KeyField ) )

INSERT INTO @ScopeTable
SELECT DISTINCT DocumentID FROM [CurrentArchive].[dbo].[ItemData]
WHERE DocumentID IS NOT NULL 

INSERT INTO [CurrentArchive].[dbo].[ItemExtras] 
SELECT TOP 1024 [ItemExtras].*
FROM [ItemExtras]
LEFT OUTER JOIN [CurrentArchive].[dbo].[ItemExtras] AS TargetTable
    ON [ItemExtras].DocumentID = TargetTable.DocumentID
INNER JOIN @ScopeTable AS ScopeTable
    ON [ItemExtras].[DocumentID] = ScopeTable.KeyField
WHERE (TargetTable.DocumentID IS NULL)

它已在许多不同的数据库上正常工作多年，但突然在一个特定的数据库上，它返回38563，这显然是“INSERT INTO @ScopeTable”部分中的行数，因为另一个插入执行“TOP” 1024" 。

是否有一些SQL Server设置可以让它改变这样的行为？依靠获得0回来是不合适的吗？

编辑：根据要求，这是运行循环的（Delphi）代码。 DataAccess.NewCommand使用TADOCommand，如果它获得异常，则返回-1：

TopClause := '';
TopCount := 2048;
Finished := false;
while not Finished do
begin
   AffectedRecords := fDataAccess.NewCommand(Format(
      '%s INSERT INTO %s SELECT%s%s [%s].* FROM [%s] %s',
      [PreClause, QualifiedTable, ManyToOneClause, TopClause, Table, Table, WhereClause]));

   if AffectedRecords >= 0 then
   begin
      if TopClause = '' then // first time through
         Finished := true
      else if AffectedRecords < TopCount then // other times through
         Finished := true;
   end
   else
   begin
      // if that fails, try top 1024, 512, etc until we reach 0 or it succeeds
      TopCount := TopCount div 2;
      if TopCount = 0 then
      begin
         fTracker.LastError := 'Failed to insert items for table ' + QualifiedTable;
         raise Exception.Create(fTracker.LastError);
      end;
      TopClause := ' TOP ' + IntToStr(TopCount);
   end;
end;

Answer 1

你可以尝试在第一次INSERT之前设置NOCOUNT，然后重新设置它：

DECLARE @ScopeTable TABLE (  KeyField bigint,  PRIMARY KEY ( KeyField ) )

SET NOCOUNT ON

INSERT INTO @ScopeTable
SELECT DISTINCT DocumentID FROM [CurrentArchive].[dbo].[ItemData]
WHERE DocumentID IS NOT NULL 

SET NOCOUNT OFF

INSERT INTO [CurrentArchive].[dbo].[ItemExtras] 
SELECT TOP 1024 [ItemExtras].*
FROM [ItemExtras]
LEFT OUTER JOIN [CurrentArchive].[dbo].[ItemExtras] AS TargetTable
    ON [ItemExtras].DocumentID = TargetTable.DocumentID
INNER JOIN @ScopeTable AS ScopeTable
    ON [ItemExtras].[DocumentID] = ScopeTable.KeyField
WHERE (TargetTable.DocumentID IS NULL)

SQL影响了一批语句的行数

1 个答案: