Hi guys,
I need an app that periodically check sql table rows and do some operations based on its values.
I have two codes to do that.
Option A
Open connection once and never close it and used it again when necessary.
Option B
Open connection before used & close connection after used.
Which option is better in performance and RAM usage?
I need an app that periodically check sql table rows and do some operations based on its values.
I have two codes to do that.
Option A
Open connection once and never close it and used it again when necessary.
B4X:
Sub Process_Globals
Private Pool1 As ConnectionPool
Private Pool2 As ConnectionPool
Private Tm As Timer
Private Qry1,Qry2,ExecQ1,ExecQ2 as SQL
end Sub
Sub AppStart (Args() As String)
Pool1.Initialize(...)
Pool2.Initialize(...)
Qry1 = Pool1.GetConnection
Qry2 = Pool2.GetConnection
ExecQ1 = Pool1.GetConnection
ExecQ2 = Pool2.GetConnection
Tm.Initialize("TM",3000)
Tm.Enabled = True
StartMessageLoop
End Sub
Sub TM_Tick
TM.Enabled = False
Private RS As ResultSet
RS = Qry1.ExecQuery("select * from table where log = 0 order by id")
Try
ExecQ1.BeginTransaction
ExecQ2.BeginTransaction
Do While RS.NextRow
'do some operations'
Loop
ExecQ1.TransactionSuccessful
ExecQ2.TransactionSuccessful
Catch
ExecQ1.Rollback
ExecQ2.Rollback
End Try
RS.Close
TM.Enabled = True
End SubOption B
Open connection before used & close connection after used.
B4X:
Sub Process_Globals
Private Pool1 As ConnectionPool
Private Pool2 As ConnectionPool
Private Tm As Timer
end Sub
Sub AppStart (Args() As String)
Pool1.Initialize(...)
Pool2.Initialize(...)
Tm.Initialize("TM",3000)
Tm.Enabled = True
StartMessageLoop
End Sub
Sub TM_Tick
TM.Enabled = False
Private Qry1,Qry2,ExecQ1,ExecQ2 as SQL
Qry1 = Pool1.GetConnection
Qry2 = Pool2.GetConnection
ExecQ1 = Pool1.GetConnection
ExecQ2 = Pool2.GetConnection
Private RS As ResultSet
RS = Qry1.ExecQuery("select * from table where log = 0 order by id")
Try
ExecQ1.BeginTransaction
ExecQ2.BeginTransaction
Do While RS.NextRow
'do some operations'
Loop
ExecQ1.TransactionSuccessful
ExecQ2.TransactionSuccessful
Catch
ExecQ1.Rollback
ExecQ2.Rollback
End Try
RS.Close
Qry1.Close
Qry2.Close
ExecQ1.Close
ExecQ2.Close
TM.Enabled = True
End SubWhich option is better in performance and RAM usage?