Can anyone speak to whether MySQL is comparable to Postgres in this area? With how quickly Postgres has been getting improvements I can't seem to tell anymore if they have feature parity or one is way out ahead of the other.
You have to be careful if you use the "rollup" way, and the event_id is assigned by a sequence. If you have two transactions, T1 and T2, and T1 inserts event_id 1000, T2 inserts event_id 1001, but T2 commits first and you run the rollup before T1 has committed you'll miss the row.
We store the txid_current() on each row, and when getting new rows we get from the previous txid up to txid_snapshot_xmin(txid_current_snapshot()).
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[ 4.3 ms ] story [ 32.7 ms ] threadWe store the txid_current() on each row, and when getting new rows we get from the previous txid up to txid_snapshot_xmin(txid_current_snapshot()).
I personally couldn't find this function, but I believe they might be talking about lastval (https://www.postgresql.org/docs/current/functions-sequence.h...).