'Example of How to use functions.

' Example use DSN created for database of Flight sample application.

SQL="SELECT * FROM ORDERS"
connection_string="QT_Flight32"

isConnected = db_connect ( curConnection ,connection_string )
If isConnected = 0 then
   ' execute the basic SQL statement
   set myrs=db_execute_query( curConnection , SQL )
   ' report the query and the connection string
   Reporter.ReportEvent micInfo ,"Executed query and created recordset ","Connection_string is ==> " & connection_string & " SQL    
query is ===> " & SQL    ' show the number of rows in the table using a record set
   msgBox " Quantity of rows in queried DB ( db_get_rows_count )==> " & db_get_rows_count( myrs )
   ' show the number of rows in the table using a new SQL statement
   msgBox " Quantity of rows in queried DB (db_get_rows_count_SQL ) ==> " & db_get_rows_count_SQL( curConnection , "SELECT COUNT(*) FROM ORDERS" )
   ' change a value of a field in an existing row
   rc = db_set_field_value (curConnection, "ORDERS" , "Agents_Name" , "test", "Agents_Name", "AGENT_TESTER")
   ' examples of how to retrieve values from the table
   msgBox "val row 0 col 0: " & db_get_field_value( myrs , 0 , 0 )
   msgBox "val row 0 col 1: " & db_get_field_value( myrs , 0 , 1 )
   msgBox "val row 1 col Name: " & db_get_field_value( myrs , 1 , "Agents_Name" )
   msgBox "val SQL row 1 col Name: " & db_get_field_value_SQL( curConnection , "ORDERS" , 1 , "Agents_Name" )
   db_disconnect curConnection
End If

' Database Functions library

'db_connect

' The function creates a new connection session to a database.
' curSession - the session name (string)
' connection_string - a connection string
' for example the connection_string can be "DSN=SQLServer_Source;UID=SA;PWD=abc123"

Function db_connect( byRef curSession ,connection_string)
   dim connection
   on error Resume next
   ' Opening connection
   set connection = CreateObject("ADODB.Connection")
    If Err.Number <> 0 then
   db_connect= "Error # " & CStr(Err.Number) & " " & Err.Description
   err.clear
   Exit Function
   End If
   connection.Open connection_string
   If Err.Number <> 0 then
   db_connect= "Error # " & CStr(Err.Number) & " " & Err.Description
   err.clear
   Exit Function
   End If
   set curSession=connection
   db_connect=0
End Function

' db_disconnect

' The function disconnects from the database and deletes the session.
' curSession - the session name (string)

Function db_disconnect( byRef curSession )
   curSession.close
   set curSession = Nothing
End Function

' db_execute_query

' The function executes an SQL statement.
' Note that a db_connect for (arg1) must be called before this function
' curSession - the session name (string)
' SQL - an SQL statement

Function db_execute_query ( byRef curSession , SQL)
   set rs = curSession.Execute( SQL )
   set db_execute_query = rs
End Function

' db_get_rows_count

' The function returns the number of rows in the record set
' curRS - variable , contain record set , that contain all values that retrieved from DB by query execution

Function db_get_rows_count( byRef curRS )
   dim rows
   rows = 0
   curRS.MoveFirst
   Do Until curRS.EOF
   rows = rows+1
   curRS.MoveNext
   Loop
   db_get_rows_count = rows
End Function

' db_get_rows_count_SQL

' The function returns the number of rows that are the result of a given SQL statement
' curSession - the session name (string)
' CountSQL - SQL statement

Function db_get_rows_count_SQL( byRef curSession ,CountSQL )
   dim cur_rs
   set cur_rs = curSession.Execute( CountSQL )
   db_get_rows_count_SQL = cur_rs.fields(0).value
End Function

' db_get_field_value_SQL

' curSession - variable denote current active connection
' tableName - name of the table , where value should be retrieved
' rowIndex - row number
' colName - the column name.

Function db_get_field_value_SQL( curSession , tableName , rowIndex , colName )
   dim rs
   SQL = " select " & colName & " from " & tableName
   set rs = curSession.Execute( SQL )
   rs.move rowIndex
   db_get_field_value_SQL = rs.fields(colName).value
End Function

' db_get_field_value

' The function returns the value of a single item of an executed query.
' Note that a db_execute_query for (arg1) must called before this function
' curRecordSet - variable , contain record set , that contain all values that retrieved from DB by query execution
' rowIndex - the row index number (zero based)
' colIndex - the column index number (zero based) or the column name.
' returned values
' -1 - requested field index more than exists in record set

Function db_get_field_value( curRecordSet , rowIndex , colIndex )
   dim curRow
   curRecordSet.MoveFirst
   count_fields = curRecordSet.fields.count-1
   If ( TypeName(colIndex)<> "String" ) and ( count_fields < colIndex ) then
   db_get_field_value = -1 'requested field index more than exists in recordset
   Else
   curRecordSet.Move rowIndex
   db_get_field_value = curRecordSet.fields(colIndex).Value
   End If
End Function

' db_set_field_value

' The function changes the value of a field according to a search criteria.
' We search for a certain row according to a column name and the desired vale, then we change a value in that row according
' to a desired columns
' curConnection - the session name (string)
' tableName - name of the table , where value should be retrieved
' colFind - the column we search the criteria in
' colFindValue - the value we search in the column
' colChange - the column were we want to change the value
' colChangeValue - the new value ' returned values

' -1 - requested field index that doesn't exists in the recordset

Function db_set_field_value(curConnection, tableName , colFind , colFindValue, colChange, colChangeValue)
   dim curRow
   dim updateSQL
   dim checkSQL
   checkSQL = "select * from Details"
   set myrs1 = db_execute_query( curConnection , SQL )
   myrs1.MoveFirst
   count_fields = myrs1.fields.count
   If ( TypeName(colFind)<> "String" ) or ( TypeName(colChange)<> "String" ) then
   db_set_field_value = -1 'requested field index that doesn't exists in the record set
   Else
   updateSQL = "UPDATE " & tableName & " SET " & colChange & "='" & colChangeValue & "' WHERE " & colFind & "='" & colFindValue &    "'"
   set myrs1 = db_execute_query( curConnection , updateSQL )
   db_set_field_value = 1 'operation suceeded
   End If
End Function

' db_add_row

' The function adds a new row to the desired table

' curConnection - variable , contains a recordset , that contains all the values to be retrieved from DB by query execution
' tableName - name of the table , where value should be retrieved from
' values - array that contains values to be entered in a new row to the table.
' Note: the function must receive values for all the columns in the table!
' returned values
' -1 - the number of values to be entered to the table doesn't fit the number of columns
' 1 - execution of the query succeed and the data was entered to the table

Function db_add_row(curConnection, tableName , byRef values)
   dim i
   dim updateSQL
   dim myrs1
   updateSQL = "INSERT INTO " & tableName & " VALUES ("
   arrLen = UBound (values) - LBound (values) + 1
   set myrs1=db_execute_query( curConnection , SQL )
   myrs1.MoveFirst
   count_fields = myrs1.fields.count
   ' check if numbers of values fit the numbers of columns
   If arrLen <> count_fields then
   db_add_row = -1
   Else
   For i = 0 to arrLen-1
   updateSQL = updateSQL & values (i)
   If i <> arrLen-1 then
   updateSQL = updateSQL & ","
   End If
   Next
   updateSQL = updateSQL & ")"
   set myrs1 = db_execute_query( curConnection , updateSQL )
   db_add_row = 1
End If
End Function

' represent_values_of_RecordSet

' the function reports all the values on fields in a record set
' curRS - variable , contains the recordset , that contains all the values that were retrieved from the DB by the query execution

Function represent_values_of_RecordSet( myrs)
dim curRowString
myrs.MoveFirst
reporter.ReportEvent 4,"Fields quantity" , myrs.fields.count
count_fields = myrs.fields.count-1
curRow=0
Do Until myrs.EOF
   curRowString= ""
   curRow = curRow+1
   For ii=0 to count_fields
   curRowString = curRowString& "Field " &"==> " & myrs.fields(ii).Name &" : Value ==>" & myrs.fields(ii).Value & vbCrLf
   Next
   myrs.MoveNext
   reporter.ReportEvent 4,"Current row"& curRow , curRowString
Loop
End Function