Mysql 是否可以更新某个列值并使用2个不同的表将其删除?
我试图做的是在第一个查询中,它将在第0列的blist表中更新。在第二次查询中,它将删除returnlist表中的选定行。您可以执行任意数量的查询。您可以这样组合查询字符串:Mysql 是否可以更新某个列值并使用2个不同的表将其删除?,mysql,datagridview,mysql-workbench,vb.net-2010,Mysql,Datagridview,Mysql Workbench,Vb.net 2010,我试图做的是在第一个查询中,它将在第0列的blist表中更新。在第二次查询中,它将删除returnlist表中的选定行。您可以执行任意数量的查询。您可以这样组合查询字符串: For k As Integer = Me.DataGridView1.SelectedRows.Count - 1 To 0 Step -1 Dim Query1 As String Query1 = "Update librarydb.b
For k As Integer = Me.DataGridView1.SelectedRows.Count - 1 To 0 Step -1
Dim Query1 As String
Query1 = "Update librarydb.blist SET quantity=(quantity + 1) where quantity = '" & Me.DataGridView1.SelectedRows(k).Cells(0).Value.ToString & "'"
command1 = New MySqlCommand(Query1, MysqlConn1)
SDA1.SelectCommand = command1
SDA1.Fill(dbDataSet1)
bSource1.DataSource = dbDataSet1
Me.DataGridView1.DataSource = bSource1
SDA1.Update(dbDataSet1)
Dim Query2 As String
For j As Integer = Me.DataGridView1.SelectedRows.Count - 1 To 0 Step -1
Query2 = "delete from returnlist where student_id= '" & Me.DataGridView1.SelectedRows(j).Cells(1).Value.ToString & "'"
command1 = New MySqlCommand(Query1, MysqlConn1)
SDA1.SelectCommand = command1
SDA1.Fill(dbDataSet1)
bSource1.DataSource = dbDataSet1
Me.DataGridView1.DataSource = bSource1
SDA1.Update(dbDataSet1)
Next
Next
所以你可以放置多个查询并执行它们,你需要用分号将它们分开
因此,您可以将两个查询合并到一个查询变量中:
"UPDATE tableA set fieldA = value; " +
"DELETE tableB WHERE fieldB = value"
然后您可以同时执行这两个命令。先生,如果您能给我一个更深入的例子,那就太好了。谢谢MySQL Systax erroir靠近28,第1.28行是Quantity的整数值。我尝试使用单个查询,只使用更新查询,但更新查询仍然不起作用。嗯,不确定错误是什么。您可以直接在mysql workbench或类似工具中运行查询吗?
Dim Query As String
Query = "delete from returnlist where quantity= '" & Me.DataGridView1.SelectedRows(k).Cells(0).Value.ToString & "'; " &
"delete from returnlist where quantity= '" & Me.DataGridView1.SelectedRows(k).Cells(0).Value.ToString & "'"