Arrays in tables and selects

This very simple example shows how to use ARRAYs in tables and in selects: create table temp.arraytest ( id bigserial, fks bigint[] ); create table temp.fks ( id bigserial, something text ); insert into temp.fks (something) values ('line1'),('line2'),('line3'); select...

Check of missing data files

If something happened and you PostgreSQL database crashed and corrupted data or your filesystem crashed and corrupted data files and you must check what is missing then you may appreciate this procedure which checks data files for every table on all databases (except...

System column ctid as row identifier

In Oracle we have system column ROWID which something like “address of the row id Oracle datafile”. This ROWID is unique because beside of table and row signature it contains also signature of datafile. Oracle stores everything in big datafiles and have...

Transaction ID wraparound

This article summarizes information I have about this problem. I know that this is not all but I did not find such a summarization anywhere therefore I place it here. Maybe it could help to someone.   Transaction ID has 32 bits. It means that after ID 2147483648 will...