Some Normal Oracle SQL Scripts

Delete column
alter table table_name drop column col_name1; -- drop one column
alter table table_name drop (col_name1, col_name2); -- drop many columns

Drop table
drop table table_name

Add column for
1.number
alter table table_name
add column_name number(10,4) NULL;

2.varchar2
alter table table_name
add column_name varchar2(10) NULL;



Edit Column name
alter table_name rename column column_name to new_colomn_name ;

sum() of column
SELECT SUM(column_name) FROM table_name

Update
UPDATE table SET column_name=value (, column_name2=value2 )WHERE xxx='yyy2';

Edit column size
ALTER TABLE table_name MODIFY (column_name varchar2(4000));