Selection and ordering

select * from tab where field='val' order by date desc;
update tab1 set field='val' where ....;

Fulltext search (need to be added as index):

select field1,field2 from tab1 where match (field3,field4) against ('+word1 +word2' in boolean mode);

Creating a new column name

select ID,Paid=='' as HasToPay from tab;