Re: Unique values on multiple tables

[John Turner <fenwayriffs@xxxxxxxxx>]

On Mon, Mar 28, 2016 at 2:32 AM, Sterpu Victor <victor@xxxxxxxx> wrote:

 

table1

id

nr - integer

 

table2

id

id_table1 - FK in Table 1

valid_from - timestamp

 

There must be unique values for:

- nr - from table1

and

- YEAR(MIN(valid_from)) from table 2

Just trying to understand your goal here -

Is 'nr' supposed to be a count of records from table2 by 'id_table1' column?

And every single value for 'nr' within table1 must be unique - i.e., you need a table of unique counts?

I think I fixed the problem by executing the function AFTER insert or update but I'm not sure.

Until now the execution was before insert or update.

That doesn't sound right, I believe you would want to stick with execution of the DML to your presumable 'fact' table (table2) using a BEFORE trigger, *especially* if it's intended to enforce constraints.

It would be helpful if you could:

• clarify/elaborate on how these 2 tables are supposed to relate to each other
  
• post your actual trigger
  
• provide us with some example inserts/updates

- John