I've been using mongodb for 2 years and many times I've faced myself asking "why should I use it for this?" or "when should I really use Mongodb?" and many other times "What did I do wrong?". Experiences, examples and real use cases many times say things that benchmarks or technical documentation don't, that for, I'll be presenting the When, Why and What of mongodb. For real, that's what really matters.

1. When?
Why?
What?
Flavio [FlaPer87] Percoco Premoli
flaper87@flaper87.org
twitter: @flaper87
domingo 8 de mayo de 2011

2. When?
domingo 8 de mayo de 2011

3. Dictionaries!
When?
domingo 8 de mayo de 2011

4. Spidering!
Dictionaries!
When?
domingo 8 de mayo de 2011

5. Statistics!
Spidering!
Dictionaries!
When?
domingo 8 de mayo de 2011

6. Queues!
Statistics!
Spidering!
Dictionaries!
When?
domingo 8 de mayo de 2011

7. Logging!
Queues!
Statistics!
Spidering!
Dictionaries!
When?
domingo 8 de mayo de 2011

8. Why?
domingo 8 de mayo de 2011

9. * Unstructured Data! (Spidering)
Why?
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10. * Lot of reads! (Dictionaries, Queues)
* Unstructured Data! (Spidering)
Why?
domingo 8 de mayo de 2011

11. * [JB]son like Document Oriented API (All)
* Lot of reads! (Dictionaries, Queues)
* Unstructured Data! (Spidering)
Why?
domingo 8 de mayo de 2011

12. * Lot of writes! (Logging, Statistics, Queues)
* [JB]son like Document Oriented API (All)
* Lot of reads! (Dictionaries, Queues)
* Unstructured Data! (Spidering)
Why?
domingo 8 de mayo de 2011

13. * Make sure you create the right indexes
# lets get our collection
collection = connection['dictionaries']['it']
def insert_word(word, data):
collection.update({'word' : word}, data, upsert=True)
What?
domingo 8 de mayo de 2011

14. * Make sure you create the right indexes
# lets get our collection
collection = connection['dictionaries']['it']
# lets ensure there’s an index for the key word
collection.ensure_index([("word", pymongo. ASCENDING)])
def insert_word(word, data):
collection.update({'word' : word}, data, upsert=True)
What?
domingo 8 de mayo de 2011

15. * Make sure you save what you really need
def parse(response):
url_netloc = urlparse.urlsplit(response.url).netloc
crawled = {
"url" : response.url,
"base_url" : url_netloc,
"content" : response.body_as_unicode(),
"status" : response.status,
"encoding" : response.encoding,
"headers" : response.headers,
"lastcrawl" : time.time(),
}
collection.update({'url' : response.url}, crawled, True)
What?
domingo 8 de mayo de 2011

16. * Make sure you understand that schemaless != mess
logs = [
{'url' : "http://www.google.com", "time" : 1304336526.011287},
{'address' : "http://www.yahoo.com", "time" : 1304336551.0424709 }
]
def insert_log()
for log in logs:
collection.insert(log)
What?
domingo 8 de mayo de 2011

17. * Make sure you understand that schemaless != mess
logs = [
{'url' : "http://www.google.com", "time" : 1304336526.011287},
{'address' : "http://www.yahoo.com", "time" : 1304336551.0424709 }
]
def insert_log()
for log in logs:
log_to_insert = {
"url" : log.get('url', log.get('address')),
"time" : log.get('time')
}
collection.insert(log_to_insert)
What?
domingo 8 de mayo de 2011

18. * “Relate” what you occasionally need, “Embed” what you always need
message = {
'msg' : "This is a test message",
'time' : time.time(),
'user' : {
'username' : 'flaper87',
'email' : 'flaper87@flaper87.org',
}
}
What?
domingo 8 de mayo de 2011

19. * ObjectIDs have an embedded datetime
def _get(self, queue):
try:
msg = self.client.database.command("findandmodify",
"messages",
query={"queue": queue},
sort={"_id": pymongo.ASCENDING}, remove=True)
except errors.OperationFailure, exc:
if "No matching object found" in exc.args[0]:
raise Empty()
raise
return deserialize(msg["value"]["payload"])
What?
domingo 8 de mayo de 2011

20. Lets talk about mongoDB!!
Thanks!!
domingo 8 de mayo de 2011

21. Thanks!!
Lets talk about mongoDB!! Thanks 10gen!!
domingo 8 de mayo de 2011