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_30234 ( "Round" text, "Clubs remaining" real, "Clubs involved" real, "Winners from previous round" text, "New entries this round" text, "Leagues entering at this round" text )

### Question ###
How many winners from previous round were there in the semi finals?

### Accurate SQL ###

SELECT "Winners from previous round" FROM table_30234 WHERE "Round" = 'Semi finals'