# Checking via pre-hook if a model should run (again)

**URL:** <https://discourse.getdbt.com/t/checking-via-pre-hook-if-a-model-should-run-again/3964>\
**Category:** Archive\
**Created:** [March 7, 2022, 12:32pm UTC](https://discourse.getdbt.com/t/checking-via-pre-hook-if-a-model-should-run-again/3964 "2022-03-07T12:32:07Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Flos](https://avatars.discourse-cdn.com/v4/letter/f/898d66/32.png) [@Flos](https://discourse.getdbt.com/u/Flos)\
**Post date:** [March 7, 2022, 12:32pm UTC](https://discourse.getdbt.com/t/checking-via-pre-hook-if-a-model-should-run-again/3964/1 "2022-03-07T12:32:07Z")

</div>

Hi all,

I want to do the following: I have a model whitch creates a table “customers”. A pre- and a post-hook is defined in the model. Both hooks should update a column in a logging table.

The logging table has a simple, four-row structure:  
tablename (varchar), run-id (number), start (timestamp), end (timestamp).

It is already filled with the following two datasets:  
‘customers’,1000,null,null  
‘customers’,2000,null,null

The pre-hook from my model should now fill the start-timestamp. The post-hook the end-timestamp after the completion of the model.

So far so easy. Now comes the tricky part.

I start the model the first time with run-id 1000. The model runs without errors and ends successfully. In the logging table, the start and end for the run-id 1000 are now \<\> null.  
I start the model a second time, again with run-id 1000. The model should NOT RUN again, because the run with run-id 1000 is already completed. To recognize that, both timestamps are not null.

Now I start the model a third time, with run-id 2000. It runs into an error and the model is aborted. In this case, only the start-timestamp is filled, the end-timestamp is still null, because the post-hook wasn’t executed.  
If I re-run this model with run-id 2000, it should run normally. Because the end-timestamp is null and the model never ran successfully for run-id 2000.

In the summary: I want to control if a model is executed by checking a logging table. If there is already a end-timestamp \<\> null for the combination tablename + run-id, the model should do nothing.

Is there a way to do that? Per model, per macro or something else?

Many thanks in advance.