Comma separated list into rows -opposite to listagg

with xxx as
(select 'a,b,c,d' col1 from dual)
select regexp_substr(col1,'[^,]+',1,level) result
from xxx
connect by level = length(regexp_replace(col1,'[^,]+')) +1;

Turns a,b,c,d
into rows
a
b
c
d

SQL Server , quick row count

SELECT T.name AS [TABLE NAME],

I.rows AS [ROWCOUNT]

FROM sys.tables AS T

INNER JOIN sys.sysindexes AS I

ON T.object_id = I.id

AND I.indid < 2

where T.name like 'mdm_frontend_export_gb1_gb2'

ORDER BY I.rows DESC

More on Bitmaps

Bitmap and other indexeing

Bitmaps and reverse indexes

Found a good source of info on stuff I have not fully understood before

reverse indexes

bitmap myths

Star transformations

https://blogs.oracle.com/optimizer/entry/star_transformation

sql developer 4 - ubuntu crahses

The answer turned out to be

ulimit -c unlimited
followed by
unset GNOME_DESKTOP_SESSION_ID

then ./sqldeveloper.sh

https://forum.java.sun.com/thread/260563

materialized view - this article sums up my view of Materialized views

http://oraclesponge.wordpress.com/2006/04/12/a-quick-materialized-view-performance-note/