LEFT -funktsiyasi asl satrning boshlang'ich satrini qaytaradi RIGHT

LEFT -funktsiyasi asl satrning boshlang'ich satrini qaytaradi
RIGHT- funktsiyasi belgilangan sondan tashkil topgan pastki qatorni qaytaradi.
select upper(nomi) from pechene;
select replace(sifat,'alo','yaxshi') from pechene;
JOINlar bilan ishlash.
SELECT
column_names [,... n]
FROM
Table_1 INNER JOIN Table_2
ON condition
SELECT
column_names [,... n]
FROM
Table_1 LEFT JOIN Table_2
ON condition
# left va inner joinlar ishlash sintaksisi
select * from pechene left join shokolad on shokolad.miqdori=pechene.miqdori;
select * from sotilgan_p right join pechene on sotilgan_p.sanasi=pechene.sanasi;

Foydalanilgan adabiyotlar:
https://www.sqlshack.com/overview-of-sql-lower-and-sql-upper-functions/
https://www.databasestar.com/sql-upper-lower/
https://www.oreilly.com/library/view/sql-in-a/9780596155322/re94.html
https://stackoverflow.com/questions/36477856/sql-select-name-no-matter-upper-
or-lower-case-letters
https://www.databasejournal.com/ms-sql/dealing-with-upper-and-lower-case-data/
https://techcommunity.microsoft.com/t5/azure-database-support-blog/sql-server-
performance-upper-and-lower-functions-and-database/ba-p/3553406
https://www.educba.com/sql-ignore-case/
Xulosa 
Bu mustaqil ishim orqali men Relatsion malumotlar bazasi haqida tushuncha oldim va
NOT, OR, AND mantiqiy standart so’zlardan foydalanishni bilib oldim. SQL da Group
by va Order by parametrlari orqali guruhlash va saralash mumkin ekan. Va SQLda bir
qancha standart funksiyalarni foydalanishni organdim.