BigSerial and txid issuance

Hi Everyone,

We’re trying to solve a problem that relies on BigSerial and txid (as returned by txid_current() ) values being issued consistently.

Is it possible for two transactions to interleave their issuance of these two variables?

For example:

Schema:

CREATE TABLE EXAMPLE(
offset bigint PRIMARY KEY GENERATED BY DEFAULT AS IDENTITY NOT NULL,
txid BIGINT NOT NULL DEFAULT 1
);

Insert statement:

"INSERT INTO EVENTS (txid) VALUES (txid_current());";

Prior to transactions executing offset is 10 and txid is 1000.

Transaction 1 and 2 occur concurrently.

Is it possible for transaction 1 to be issued txid 1001 and offset 12 and transaction 2 to be issued txid 1002 and offset 11?

Any help would be much appreciated.

Regards,

Adam
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