Progress bar is run-time SQL-query progress indicator.

Function pg_progress_bar(pid) extracts the current query state from backend with specified 'pid'. Then gets the
numerical values of the actual rows and total rows and count progress for the whole query tree. Function returns
numeric value from 0 to 1 describing the measure of query fulfillment. This function can be used to be embedded
in the PostgreSQL GUI.

To intuitively track progress without using a graphical client, you can use the additionally implemented function
pg_progress_bar_visual(pid, delay). It prints state every period specified by 'delay' (in seconds).

Increase version to 1.2 due to init.sql change.

• Commit c927d0c
• Compare b3ae98e..c927d0c
• Branch master

Ekaterina Sokolova