MySQL: INDEXES are awesome

#mysql #tutorial #course

— INDEX (BTree data structure)
— Indexes are used to find values within a specific column more quickly
— MySQL normally searches sequentially through a column
— The longer the column, the more expensive the operation is
— UPDATE takes more time, SELECT takes less time

— Single column index
CREATE INDEX last_name_idx
ON customers (last_name);

— Multi column index
CREATE INDEX last_name_first_name_idx
ON customers (last_name, first_name);