B4J Question Execution time

[bogdanc]

Hi All.

How to get the execution time of sub.
For example i want to check execution time of mysql.

Thanks

 

[Erel]

Dim n As Long = DateTime.Now
'more code here

Log("Took: " & (DateTime.Now - n) & " ms")

Tips for SQL:
1. Use transactions.
2. Use async methods if the database is not local.

 

[bogdanc]

Thank You Erel.
I did as You suggested.

I'm using jSQL module to talk with my database.

I used a timer to query DB for periodical check (every 5sec).

Main:

Sub Interval_query_tick
TextField2.Text=mysql1.DB_GET_RESPOND
End Sub

On module class mysql:

Sub DB_GET_RESPOND
    Dim n As Long= DateTime.Now   
    Dim Cursor2 As ResultSet
    Cursor2 = sql1.ExecQuery("SELECT KEY FROM prod.main ORDER BY prod.KEY DESC LIMIT 1")
    Do While Cursor2.NextRow
        Return  (( DateTime.Now-n) * 0.001)
    Loop
End Sub

Is it a better way to query and get execution / respond time?


I want check 2 data bases on same time.
I was thinking to use 2 timers one per DB.

is it a good idea?

 

[Erel]

I don't think that your code does anything useful.

It will return after the first iteration. What exactly are you trying to do? Is there something slow that you are trying to optimize?

 

[bogdanc]

Hi Erel!

I'm trying to check respond from mysql server.
I have some issue and I need to build app to check if is server responding quickly or not.
Is is any beer solution to check mysql db performance.
I want to build it with B4J.

 

[Erel]

The code should be:

Sub DB_GET_RESPOND As Double
    Dim n As Long= DateTime.Now  
    Dim Cursor2 As ResultSet = sql1.ExecQuery("SELECT KEY FROM prod.main ORDER BY prod.KEY DESC LIMIT 1")
    Cursor2.Close
    Return  (( DateTime.Now-n) * 0.001)
End Sub

1. Add a Try / Catch block to catch any errors.
2. It is better to use sql1.ExecQueryAsyc to avoid blocking the UI. It will be a bit more complicated.

 

[bogdanc]

Hi Erel!

Ad1)
I modified to:

    Dim n As Long= DateTime.Now   
    Try
    Dim Cursor2 As ResultSet  = sql1.ExecQuery("
"SELECT KEY FROM prod.main ORDER BY prod.KEY DESC LIMIT 1"
")
     Cursor2.Close
    Log("TS Time exec [s]:" &  (( DateTime.Now-n) * 0.001))
    Return  (( DateTime.Now-n) * 0.001)
    Catch
        Log("ERROR:"& Cursor2)
        Return "Tesstabd error"& Cursor2
    End Try

I added try and catch.

Ad)

Is there any tutorial to shows how to use ExecQueryAsyc?


Thanks

 

[Erel]

See the B4A tutorial: SQL tutorial
It is the same as in B4J.