I think I have a performance problem for a simple select with range. My Tables: CREATE TABLE locations( locid INTEGER PRIMARY KEY, country TEXT, region TEXT, city TEXT, postalCode TEXT, latitude REAL, longitude REAL, dmaCode INTEGER, areaCode INTEGER)
CREATE TABLE blocks( startIpNum INTEGER, endIpNum INTEGER, locId INTEGER) My Data: http://www.maxmind.com/app/geolitecity Blocks table has 2,776,436 rows Locations table has 159,488 rows After inserting the data I run analyze. My Query: select * from blocks,locations where locations.locid = blocks.locid AND ? >= blocks.startIpNum AND ? <= blocks.endIpNum (replace ? with a number) Disclaimer: I'm a bit new to databases. Performance issues: I use python's sqlite3 module to run the query. With this configuration it takes about 0.6 seconds to complete the query. I think this is too slow. I could write a binary tree myself and have searches like this take, O(log(num_rows)) which is 7*something_which_shouldnt_take_too_much. Am I wrong? (see the disclaimer) Anyway, I thought the problem was that startIpNum, endIpNum are not indexed. So I added indices for them (even tried indexing them both). This only makes the query take about 3 seconds. Ideas anyone? Source: is attached. Thank you for your help -- Dani http://daniva.googlepages.com -- Dani http://daniva.googlepages.com
'''geolite GeoLite City is a free IP to city database provided by MaxMind. They provide a C API (and a python wrapper) for the database. If you can't compile the C sources on your server (or get a binary version), this script might be helpful for you. The script puts the geoip data in a sqllite database, and provides interfaces for updating and searching the database. To use this script, get the database in CSV format: http://www.maxmind.com/app/geolitecity You also need to have python 2.5 for this script (sqlite3 is used) ''' import sqlite3 as sqlite import os def dottedQuadToNum(ip): "convert decimal dotted quad string to long integer" hexn = ''.join(["%02X" % long(i) for i in ip.split('.')]) return long(hexn, 16) def cursorToDict(cursor): val = cursor.next() return dict([(cursor.description[i][0],val[i]) for i in xrange(len(cursor.description))]) def test(): import sqlite3 from time import clock x = sqlite3.connect('geolite.db') y = x.cursor() ip = dottedQuadToNum("84.108.189.94") res = y.execute('select * from blocks,locations where locations.locid = blocks.locid AND ? >= blocks.startIpNum AND ? <= blocks.endIpNum', [ip,ip]) begin = clock() f = res.next() end = clock() y.close() x.close() return end-begin, f def test2(): from time import clock x = GeoLiteDB() x.connect(); begin = clock() x.ipLocation("84.108.189.94"); end = clock() x.close() return end - begin def createDB(dbPath = 'geolite.db', locationsPath='GeoLiteCity-Location.csv', blocksPath='GeoLiteCity-Blocks.csv', warnOnDelete = True): if os.path.exists(dbPath): if warnOnDelete: print "file %s will be deleted. Press any key to continue, or 'n' to abort..." % (os.path.abspath(dbPath)) if getch() == 'n': print 'aborted.' return None os.remove(os.path.abspath(dbPath)) conn = sqlite.connect(dbPath) cursor = conn.cursor() try: cursor.execute('''CREATE TABLE locations( locid INTEGER PRIMARY KEY, country TEXT, region TEXT, city TEXT, postalCode TEXT, latitude REAL, longitude REAL, dmaCode INTEGER, areaCode INTEGER)''') cursor.execute('''CREATE TABLE blocks( startIpNum INTEGER, endIpNum INTEGER, locId INTEGER)''') locations = file(locationsPath,'r') print ('parsing locations. This will a while.') print locations.readline().strip() #should print copyright note print locations.readline().strip() #should print column names lines = ([x.strip('"') for x in line.strip().split(',')] for line in locations.xreadlines()) cursor.executemany('insert into locations values (?,?,?,?,?,?,?,?,?)', lines) locations.close() blocks = file(blocksPath,'r') print ('parsing blocks. This will take longer.') print blocks.readline().strip() #should print copyright note print blocks.readline().strip() #should print column names lines = ([x.strip('"') for x in line.strip().split(',')] for line in blocks.xreadlines()) cursor.executemany('insert into blocks values (?,?,?)', lines) blocks.close() # cursor.execute('''CREATE UNIQUE INDEX startIpNumIx ON blocks(startIpNum);''') # cursor.execute('''CREATE UNIQUE INDEX endIpNumIx ON blocks(endIpNum);''') conn.commit() print 'analyze' cursor.execute('''ANALYZE;''') numBlocks = cursor.execute('select count(*) from blocks').fetchone()[0] numLocations = cursor.execute('select count(*) from locations').fetchone()[0] return numBlocks, numLocations finally: cursor.close() conn.close() class GeoLiteDB: def __init__(self, dbPath = 'geolite.db'): self.dbPath = dbPath self._conn = None self._cursor = None def connect(self): if self._conn: raise 'database already opened' self._conn = sqlite.connect(self.dbPath) self._cursor = self._conn.cursor() def close(self): if not self._conn: raise 'databse was not opened' self._cursor.close() self._conn.close() def autoConnect(self): if not self._conn: self.connect() def countBlocks(self): self.autoConnect() return self._cursor.execute('select count(*) from blocks').next()[0] def countLocations(self): self.autoConnect() return self._cursor.execute('select count(*) from locations').next()[0] def ipLocation(self, ip): self.autoConnect() if isinstance(ip,str): ip = dottedQuadToNum(ip) return cursorToDict(self._cursor.execute('select * from blocks,locations where locations.locid = blocks.locid AND ? >= blocks.startIpNum AND ? <= blocks.endIpNum', [ip,ip])) #cross platform getch, from http://aspn.activestate.com/ASPN/Cookbook/Python/Recipe/134892 class _Getch: """Gets a single character from standard input. Does not echo to the screen.""" def __init__(self): try: self.impl = _GetchWindows() except ImportError: self.impl = _GetchUnix() def __call__(self): return self.impl() class _GetchUnix: def __init__(self): import tty, sys def __call__(self): import sys, tty, termios fd = sys.stdin.fileno() old_settings = termios.tcgetattr(fd) try: tty.setraw(sys.stdin.fileno()) ch = sys.stdin.read(1) finally: termios.tcsetattr(fd, termios.TCSADRAIN, old_settings) return ch class _GetchWindows: def __init__(self): import msvcrt def __call__(self): import msvcrt return msvcrt.getch() getch = _Getch()
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