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c# - 如何将多个 SQL 命令合二为一？

问题描述

是否可以通过将以下查询合并到单个 SQLCommand 中来优化它们？

SqlCommand cmd = new SqlCommand
{
    CommandType = CommandType.Text,
    CommandText = "DELETE FROM cbu_naslovi WHERE [ID]='" + CurrentID + "'",
    Connection = con
};
SqlCommand cmd1 = new SqlCommand
{
    CommandType = CommandType.Text,
    CommandText = "DELETE FROM cbu_deli WHERE [IDX]='" + CurrentID + "'",
    Connection = con
};
cmd.ExecuteNonQuery();
cmd1.ExecuteNonQuery();

编辑：工作解决方案，正如社区答案所建议的那样

SqlCommand cmd = new SqlCommand
{
    CommandType = CommandType.Text,
    CommandText = "DELETE FROM cbu_naslovi WHERE [ID] = @CurrentID; DELETE FROM cbu_deli WHERE [IDX] = @CurrentID",
    Connection = con
};
cmd.Parameters.AddWithValue("@CurrentID", CurrentID);
cmd.ExecuteNonQuery();

标签： c#sqlwpf

解决方案

是的，您可以用分号分隔它们。例如，我有在一次调用中执行以下代码的代码

SET NOCOUNT ON;
DECLARE @decimalDate DECIMAL(12,0);
DECLARE @charDate CHAR(12);
DECLARE @utcDate DATETIMEOFFSET;
DECLARE date_cursor CURSOR FOR SELECT {1} FROM {0} WHERE ISNULL({1},0)!=0;
OPEN date_cursor;
FETCH NEXT FROM date_cursor INTO @decimalDate;
WHILE @@FETCH_STATUS=0
BEGIN
    BEGIN TRY SET @charDate=CONVERT(CHAR(12),@decimalDate);
        SET @utcDate=SwitchOffset(
                CONVERT(DATETIME,'20'
                    +SUBSTRING(@charDate,1,2)+'-'+SUBSTRING(@charDate,3,2)+'-'
                    +SUBSTRING(@charDate,5,2)+' '+SUBSTRING(@charDate,7,2)+':'
                    +SUBSTRING(@charDate,9,2)+':'+SUBSTRING(@charDate,11,2)
                ,121) AT TIME ZONE '{3}',0);
    END
    TRY BEGIN CATCH
        SET @utcDate=SysUtcDateTime();
    END CATCH;
    BEGIN
        TRY UPDATE {0} SET {2}=@utcDate WHERE CURRENT OF date_cursor;
    END TRY
    BEGIN CATCH END CATCH;
    FETCH NEXT FROM date_cursor INTO @decimalDate;
END;
CLOSE date_cursor;
DEALLOCATE date_cursor;

也有例外。例如，“创建过程”语句必须是块的第一条语句。但是大多数 DML 都可以像这样进行批处理。

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