Hey Jeff, I would recommend to go in the
https://stackoverflow.com/ or even going to Microsoft or Oracle depending on DB you're going to work with. If you're focusing to the functional side of it, you will be just fine, it is quite simple actually. But let me know if you are looking for something more advanced when performing the SQLs.
Some tips:
When building a select with multiple tables, make sure you have the proper keys in the Join like
Select GLDOC, GLDCT, GLKCO, GMDL01 from xxxdta.f0901, xxx.dtaF0911
where GLAID = GMAID and xxx xxxx xxxx xxxx xxx
Date from Julian to Gregorian date MS SQL
CONVERT(VARCHAR(8),DATEADD(year, cast(F0911.GLDGJ as int) / 1000, 0)
+ DATEADD(day, cast(F0911.GLDGJ as int) % 1000, 0) - 1, 112) as GLDATE,
Same but for Oracle DB:
TO_DATE(TO_CHAR(F0911.GLGDJ+1900000),'YYYYDDD') AS GLDate,
You can also use the
http://www.jdetables.com/ to read all tables design as you need.
Good luck