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_53327 ( "Unit" text, "Reactor Type" text, "Net Capacity" text, "Gross Capacity" text, "Construction Start" text, "Grid Connection" text, "Commercial Operation" text, "Status" text )

### Question ###
When was the Hamaoka-4 unit commercial operation date?

### Accurate SQL ###

SELECT "Commercial Operation" FROM table_53327 WHERE "Unit" = 'hamaoka-4'