support possibility of empty patch field in the database
support possibility of empty patch field in the database

sagemathinc/smc,DrXyzzy/smc,DrXyzzy/smc,tscholl2/smc,tscholl2/smc,sagemathinc/smc,tscholl2/smc,sagemathinc/smc,sagemathinc/smc,tscholl2/smc,DrXyzzy/smc,tscholl2/smc,DrXyzzy/smc