postgresql is incrementing an update by 2?

I'm migrating our model to postgresql for the FTS and data integrity

update myschema.counters set counter_count= (counter_count+1) where counter_id =?

Work开发者_如何学运维s as expected in mysql, however in postgres it is incrementing by 2 each time? It is simple int field I believe, I don't have anything special going on.

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You should use a sequence to populate the value.

CREATE SEQUENCE counter_seq START 1;

UPDATE myschema.counters 
   SET counter_count = NEXTVAL('counter_seq')
 WHERE counter_id = ?