ЭCREATE TABLE [category] ("+
 "[_id] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,"+
 "[NameCat] CHAR(50)

"CREATE TABLE [tariff] ("+
 "[_id] INTEGER NOT NULL PRIMARY KEY AUTOINCREMENT,"+
 "[_IDCat] INTEGER NOT NULL CONSTRAINT [FK_IDCat] REFERENCES [category]([_ID]) ON DELETE CASCADE,"+
 "[Tariff] FLOAT(12, 2) NOT NULL);

private SQLiteDatabase mDB; 

public Integer delDataByIDCategory(Long id)
 {   
   return mDB.delete(TBL_CATEGORY, TBL_CATEGORY_ID+" = "+id.toString(), null);	 
 }