Regex to capture multiple groups of SELECT queries in a single statement with 0 or more UNIONs?

Question

I have a list of SQL queries which can range from a simple

SELECT * from ABC

to complex ones like

SELECT A,B,C from ABC Where Z=5 and T=10 UNION SELECT * from GHI Where i=100 UNION SELECT X,Y from XYZ

I would like to capture the bold sections using a regex. Currently, I have (SELECT[\\s]*.*from[\\s]*) but this treats the 2nd query as a single SELECT query ie SELECT .... from XYZ while I need it to find 3 parts highlighted above.

Can someone pls kindly offer some advice? Thanks.

Answer 1

The following pattern should work in pretty much any language in case-insensitive mode:

SELECT\s(?:(?!FROM)[\s\S])*\sFROM

This even works when the SQL code spreads across multiple lines.

Demo

Alternatively, enable single-line mode and just use a dot: SELECT\\s(?:(?!FROM).)*\\sFROM .