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_17864 ( "Constituency" text, "Electorate" real, "s Spoilt vote" real, "Total poll (%)" text, "For (%)" text, "Against (%)" text )

### Question ###
List the smallest possible spoilt vote with the s r-tr ndelag constituency.

### Accurate SQL ###

SELECT MIN("s Spoilt vote") FROM table_17864 WHERE "Constituency" = 'Sør-Trøndelag'