This script is designed to help reset all sequences in a PostgreSQL database to their correct values based on existing data in the tables.
In PostgreSQL, sequences are used to auto-increment integer columns in tables. These sequences need to have their "last value" accurately set to avoid conflicts when inserting new rows into the table. This can become an issue, for example, when data is imported into the database and the sequences are not updated accordingly, leading to unique constraint
The script works by iterating over each table in the current schema of the PostgreSQL database. For each table, it dynamically looks up the associated sequence and the column that the sequence is used for. It then finds the maximum value in that column and sets the "last value" of the sequence to this maximum value.