Question

我试图为我创建一种方法，同时在多个表中应用truncate。

我尝试了以下代码：

SELECT CONCAT('TRUNCATE TABLE ',table_schema,'.',TABLE_NAME, ';')
 FROM INFORMATION_SCHEMA.TABLES
 WHERE table_schema in ('mytable1','mytable2','mytable3');

更不成功的是，它没有截断表格。

有谁知道有任何方法可以做到这一点？

Answer 1

如果你想让它保持原子状态，请使用事务来完成。

Dim Sale_Amount, Sales_Tax_Rate, Sales_Tax_Amount, Total_Price
Dim MySheet, RowCount, i

'Create connection b/w UFT and Excel
Set MyExcel = CreateObject("Excel.Application")
MyExcel.Workbooks.Open "C:\Users\PIIT\Desktop\UFT\BootCamp2\BootCamp2 Question 4.xlsx"
MyExcel.Application.Visible = True
Set MySheet = MyExcel.ActiveWorkbook.Worksheets ("Sheet1")
RowCount = MySheet.UsedRange.Rows.Count

For i = 2 To RowCount
    'Read Values from Excel
    Sale_Amount = MySheet.Cells(i, "A").Value
    Sales_Tax_Rate = MySheet.Cells(i, "B").Value

    'Call Function
    fnTax_Calculator
Next

Function fnTax_Calculator()
    Dim Arry(1)
    'Function should return Sales_Tax_Amount when it is called in the form of %x.xx
    Sales_Tax_Amount = Sale_Amount * Sales_Tax_Rate
    'Function should return Total_Price when it is called in the form of $xxxx.xx
    Total_Price = Sale_Amount + Sales_Tax_Amount

    Arry(0) = Sales_Tax_Amount
    Arry(1) = Total_Price
End Function

Answer 2

DECLARE @CODE NVARCHAR(MAX) = '', @XML XML

SET @XML = STUFF((
            SELECT ' ' + data.CODE_DELETE
            FROM (
                SELECT CONCAT ('TRUNCATE TABLE ', table_schema, '.', TABLE_NAME, '') AS CODE_DELETE
                FROM INFORMATION_SCHEMA.TABLES
                WHERE TABLE_NAME IN ('CITY', 'WORKERS')
                ) [data]
            FOR XML PATH('')
            ), 1, 1, '')
SET @CODE = CAST(@XML AS VARCHAR(MAX))

SELECT @CODE

EXECUTE sp_executesql @CODE;

变量@XML是能够将行转换为单个值，然后我们必须将sql代码转换为varchar才能执行它 EXECUTE sp_executesql @CODE;

您可以看到执行此操作时将执行的代码：

SELECT @CODE

city和workers是我在数据库中的表格，如果您看起来我在table_schema子句中将TABLE_NAME更改为WHERE。

在多个表中截断

2 个答案: