--- a/python/storage.py	Thu Jul 23 09:31:47 2015 -0400
+++ b/python/storage.py	Fri Jul 24 17:58:59 2015 -0400
@@ -34,19 +34,47 @@
     except sqlite3.OperationalError as error:
         printDBError(error)
 
-def createIndex(filename, tableName, columnName, createAnyway = False):
+def createIndex(connection, tableName, columnName, unique = False):
     '''Creates an index for the column in the table
     I will make querying with a condition on this column faster'''
     try:
-        connection = sqlite3.connect(filename)
+        #connection = sqlite3.connect(filename)
         cursor = connection.cursor()
-        if createAnyway:
-            notExists = ""
+        s = "CREATE "
+        if unique:
+            s += "UNIQUE "
+        cursor.execute(s+"INDEX IF NOT EXISTS "+tableName+"_"+columnName+"_index ON "+tableName+"("+columnName+")")
+        connection.commit()
+        #connection.close()
+    except sqlite3.OperationalError as error:
+        printDBError(error)
+
+def getNumberRowsTable(connection, tableName, columnName = None):
+    '''Returns the number of rows for the table
+    If columnName is not None, means we want the number of distinct values for that column
+    (otherwise, we can just count(*))'''
+    try:
+        cursor = connection.cursor()
+        if columnName is None:
+            cursor.execute("SELECT COUNT(*) from "+tableName)
         else:
-            notExists = "IF NOT EXISTS "
-        cursor.execute("CREATE INDEX "+notExists+tableName+"_"+columnName+"_index ON "+tableName+"("+columnName+")")
-        connection.commit()
-        connection.close()
+            cursor.execute("SELECT COUNT(DISTINCT "+columnName+") from "+tableName)
+        return cursor.fetchone()[0]
+    except sqlite3.OperationalError as error:
+        printDBError(error)
+
+def getMinMax(connection, tableName, columnName, minmax):
+    '''Returns max/min or both for given column in table
+    minmax must be string max, min or minmax'''
+    try:
+        cursor = connection.cursor()
+        if minmax == 'min' or minmax == 'max':
+            cursor.execute("SELECT "+minmax+"("+columnName+") from "+tableName)
+        elif minmax == 'minmax':
+            cursor.execute("SELECT MIN("+columnName+"), MAX("+columnName+") from "+tableName)
+        else:
+            print("Argument minmax unknown: {}".format(minmax))
+        return cursor.fetchone()[0]
     except sqlite3.OperationalError as error:
         printDBError(error)