Question

对postgresql数据库进行非常简单的更新，但它无法正常工作。 sql select语句很好，并返回正确的值。

当我进入更新时，它会抛出错误：

 {"ERROR [0A000] ERROR: cross-database references are not implemented: "openerp.public.product_template"; Error while executing the query"}.

我正在使用vb.net和postgresql 9.2。

我想要它做的就是更改名称字段以匹配说明中的内容。

log:
LOG 0   duration: 34.000 ms  statement: SELECT * FROM product_template where import_date = '08/22/2013'
LOG 0   duration: 11.000 ms  statement: select n.nspname, c.relname, a.attname, a.atttypid, t.typname, a.attnum, a.attlen, a.atttypmod, a.attnotnull, c.relhasrules, c.relkind, c.oid, d.adsrc from (((pg_catalog.pg_class c inner join pg_catalog.pg_namespace n on n.oid = c.relnamespace and c.oid = 20496) inner join pg_catalog.pg_attribute a on (not a.attisdropped) and a.attnum > 0 and a.attrelid = c.oid) inner join pg_catalog.pg_type t on t.oid = a.atttypid) left outer join pg_attrdef d on a.atthasdef and d.adrelid = a.attrelid and d.adnum = a.attnum order by n.nspname, c.relname, attnum
LOG 0   duration: 12.000 ms  parse _PLAN000000001D2CFB60: SELECT * FROM product_template where import_date = '08/22/2013'
LOG 0   duration: 11.000 ms  statement: select ta.attname, ia.attnum, ic.relname, n.nspname, tc.relname from pg_catalog.pg_attribute ta, pg_catalog.pg_attribute ia, pg_catalog.pg_class tc, pg_catalog.pg_index i, pg_catalog.pg_namespace n, pg_catalog.pg_class ic where tc.oid = 20496 AND tc.oid = i.indrelid AND n.oid = tc.relnamespace AND i.indisprimary = 't' AND ia.attrelid = i.indexrelid AND ta.attrelid = i.indrelid AND ta.attnum = i.indkey[ia.attnum-1] AND (NOT ta.attisdropped) AND (NOT ia.attisdropped) AND ic.oid = i.indexrelid order by ia.attnum
LOG 0   duration: 0.000 ms  statement: select current_schema()
LOG 0   duration: 1.000 ms  statement: select c.relhasrules, c.relkind, c.relhasoids from pg_catalog.pg_namespace u, pg_catalog.pg_class c where u.oid = c.relnamespace and c.relname = 'product_template' and u.nspname = 'public'
LOG 0   duration: 1.000 ms  statement: select c.relhasrules, c.relkind, c.relhasoids from pg_catalog.pg_namespace u, pg_catalog.pg_class c where u.oid = c.relnamespace and c.relname = 'product_template' and u.nspname = 'public'
ERROR   0A000   cross-database references are not implemented: "openerp.public.product_template"

代码：

Private Sub btnChgNameToDescr_Click(sender As Object, e As EventArgs) Handles btnChgNameToDescr.Click

    Dim objConn As New System.Data.Odbc.OdbcConnection
    Dim objCmd As New System.Data.Odbc.OdbcCommand
    Dim dtAdapter As New System.Data.Odbc.OdbcDataAdapter
    Dim ds As New DataSet

    Me.Cursor = System.Windows.Forms.Cursors.WaitCursor

    Dim strConnString As String
    Dim strSQL As String
    Dim iRecCount As Integer

    Me.Cursor = System.Windows.Forms.Cursors.WaitCursor

    If objConn.State = ConnectionState.Open Then
        'do nothing
    Else
        strConnString = "Dsn=PostgreSQL35W;database=OpenERP;server=localhost;port=5432;uid=openpg;pwd=openpgpwd"
        objConn.ConnectionString = strConnString
        objConn.Open()
    End If


    If Me.txtImportDate.Text = "" Then
        MsgBox("Import Date field cannot be blank.")
        Exit Sub
    End If

    Dim str_import_date As String = Me.txtImportDate.Text


    strSQL = "SELECT * FROM product_template where import_date = " & "'" & str_import_date & "'"

    dtAdapter.SelectCommand = objCmd

    With objCmd
        .Connection = objConn
        .CommandText = strSQL
        .CommandType = CommandType.Text
        .ExecuteNonQuery()

        dtAdapter.Fill(ds, "product_template")

        iRecCount = ds.Tables("product_template").Rows.Count

    End With

    If iRecCount = 0 Then
        MsgBox("No records found.")
        Me.Cursor = System.Windows.Forms.Cursors.Default
        Exit Sub
    End If


    Dim cb As New Odbc.OdbcCommandBuilder(dtAdapter)


    'change the name field to item_description
    With ds
        For i As Integer = 0 To .Tables("product_template").Rows.Count - 1

            'this works, returns a string
            Dim str_default_code As String = (.Tables(0).Rows(i).Item("name").ToString)
            'this works
            Dim str_item_description As String = (.Tables(0).Rows(i).Item("description").ToString)

            .Tables("product_template").Rows(i).Item("name") = str_item_description
            'setting the variable doesn't work either - Dim str_item_description As String = "BH LITE BRT"

            'this throws the error
            dtAdapter.Update(ds, "product_template")

        Next
    End With

    Me.Cursor = System.Windows.Forms.Cursors.Default
End Sub

Answer 1

在postgresql日志中查找错误，以查看实际发送到数据库的内容。我不知道如何修复您的代码，因为我不太了解该平台。此外，您需要转到参数化查询，因为您当前的方法将受到SQL注入问题的影响。

但是，您的错误意味着您有一个额外的命名空间。正常的命名空间是schema.table.column或schema.table，具体取决于上下文。如果您尝试将表指定为schema.table.column，则会将其读为database.schema.table并抛出此错误。同样，如果你有一个额外的点，你可能会意外地指定database.schema.table.column（这也会引发错误）。

这是为什么字符串化SQL真的是一个坏主意的一个原因，但并不是真正划伤问题的表面。

Answer 2

我在使用 DataGrip（2020.3 版）时遇到了同样的问题。

就我而言，这是因为我更改了连接设置，但一直使用相同的控制台窗口。

我找到了两种方法来解决这个问题：

更改控制台的会话（在控制台中右键单击--> 切换会话--> 新会话）
打开一个新的控制台窗口

Answer 3

今天正在做某事并且得到了-最终是因为我的数据库名称中包含大写字母，而命令没有-prodCRT.public.tablename与prodcrt.public.tablename

我将架构重命名为小写字母后，我以前使用过的所有命令都再次起作用。

注意：原始数据库仅被称为“ prod”-所以当我将其称为prodCRT时事情就崩溃了

为什么我得到“跨数据库引用未实现”？

3 个答案: