How is the level of isolation of serializable transactions implemented in PostgreSQL?

In PostgreSQL, the SERIALIZABLE transaction isolation level is implemented using Multi-Version Concurrency Control (MVCC) and additional conflict detection mechanisms.

When executing transactions at the SERIALIZABLE level, PostgreSQL tracks all read and write operations to ensure that the outcome is equivalent to some serial order of transaction execution.

If a conflict occurs, such as two transactions trying to modify the same data or one transaction reading data that another modifies, PostgreSQL may abort one of the transactions with a serialization failure to prevent anomalies.

In Go, you can set the isolation level for PostgreSQL using drivers like database/sql with lib/pq, by executing an SQL command:

_, err := db.Exec("SET TRANSACTION ISOLATION LEVEL SERIALIZABLE")
if err != nil {
    // handle error
}

Thus, the SERIALIZABLE level in PostgreSQL provides strict transaction isolation, preventing issues related to concurrent data access.