index in mysql code example

Example 1: create index mysql

create index your_index_name on your_table_name(your_column_name) using HASH;
or
create index your_index_name on your_table_name(your_column_name) using BTREE;

Example 2: mysql select statement after index

SELECT * FROM table1 USE INDEX (col1_index,col2_index)
    WHERE col1=1 AND col2=2 AND col3=3;