I have been trying to get datatype of a column by passing the column name as parameter in following code part. But my query returns "unknown" value instead of defined datatypes like character varying, integer, text, etc. If I give paramater value directly into SQL query instead of question mark (?), it returns what I want to see. ("SELECT pg_typeof(haendler_id) from t_haendler limit 1;"). How can I handle this problem?
Sub PGTYPEOF()
Dim CN As New ADODB.Connection
Dim RS As New ADODB.Recordset
Dim CM As New ADODB.Command
Dim PM1 As New ADODB.Parameter
Dim strConn As String
Dim i, ItemVal As Variant
strConn = "Driver={PostgreSQL ODBC Driver(Unicode)};DSN=postgres;Server=localhost;
Port=5432;UID=postgres;PWD=###; Database=###;READONLY=0;PROTOCOL=6.4;FAKEOIDINDEX=0;
SHOWOIDCOLUMN=0; ROWVERSIONING=0;SHOWSYSTEMTABLES=1"
CN.Open strConn
i = "haendler_id"
With CM
.ActiveConnection = CN
.CommandText = "SELECT pg_typeof(?) from t_haendler limit 1;"
.CommandType = adCmdText
Set PM1 = .CreateParameter(, adVarChar, adParamInput, 30)
PM1.Value = i
.Parameters.Append PM1
Set RS = .Execute
End With
Do While Not RS.EOF
'Debug.Print RS.Fields(0).Value
ItemVal = RS.Fields(0).Value
RS.MoveNext
Loop
End Sub
I do not know why but pg_typeof() function does not function. I solved my problem changing my sql query as follows "select data_type from information_schema.columns where table_name = ? and column_name = ?;"
With CM
.ActiveConnection = CN
.CommandText = "select data_type from information_schema.columns where
table_name = ? and column_name = ?;"
.CommandType = adCmdText
Set PM1 = .CreateParameter(, adVarChar, adParamInput, 30)
PM1.Value = i
.Parameters.Append PM1
Set PM2 = .CreateParameter(, adVarChar, adParamInput, 30)
PM2.Value = j
.Parameters.Append PM2
Set RS = .Execute
End With
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