How do I improve the performance of my system because it is very slow and worsens with each day that new data is inserido.Observei here in the forum many people with the same problem. What I found was more tips for using an index, but how do I use.
Would post some example of two tables using LEFT OUTER JOIN to a common field.
I'm new and do not have much experience and my English sucks.
thank you
SQL Query much slower