Below is the list of tables from the database along with their columns and datatype. Need to generate an accurate SQL query for the question.
Only use the columns present in the respective table. Only use the columns which are required to generate the SQL query. Only use table joins if required and not otherwise.

### Tables ###
TABLE: CREATE TABLE table_22754491_1 ( margin VARCHAR, constituency VARCHAR )

### Question ###
What is the margin when periyakulam is the constituency?

### Accurate SQL ###

SELECT margin FROM table_22754491_1 WHERE constituency = "Periyakulam"