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_12423 ( "Constituency number" text, "Name" text, "Reserved for ( SC / ST /None)" text, "District" text, "Number of electorates (2009)" real )

### Question ###
Name the District that has a Reserved for ( SC / ST /None) of none and a Constituency number of 242?

### Accurate SQL ###

SELECT "District" FROM table_12423 WHERE "Reserved for ( SC / ST /None)" = 'none' AND "Constituency number" = '242'