connection-pooling

I just wanted to know the concept of database connection pooling and how it is achieved. Database connection pooling is a method used to keep database connections open so they can be reused by others. Typically, opening a database connection is an expensive operation, especially if the database is remote. You have to open up network sessions, authenticate, have authorisation checked, and so on. Pooling keeps the connections active so that, when a connection is later requested, one of the active ones is used in preference to having to create another one. Refer to the following diagram for the

We have some client code which is using the SqlConnection class in .NET to talk to a SQLServer database. It is intermittently failing with this error: "ExecuteReader requires an open and available Connection. The connection's current state is Closed" The "temporary" solution is to reboot the process, after which everything works - however, that's obviously unsatisfactory. The code is keeping a cache of SqlConnection instances, one for each database. We'd like to re-write the code, but before I do, I need to know a few things: My first question is: Is it inefficient to repeatedly connect and

I'm trying to set up a MySQL connection pool and have my worker processes access the already established pool instead of setting up a new connection each time. I'm confused if I should pass the database cursor to each process, or if there's some other way to do this? Shouldn't MySql.connector do the pooling automatically? When I check my log files, many, many connections are opened and closed ... one for each process. My code looks something like this: PATH = "/tmp" class DB(object): def __init__(self): connected = False while not connected: try: cnxpool = mysql.connector.pooling

Does anybody have experience with using Oracle UCP under real production load? Does it handle database reconnects well? Are there any multi-threading issues? Has anybody compared it with C3P0 or Apache DBCP? MRalwasser I evaluated UCP 11.2.0.1 as a replacement for our legacy connection pool and I cannot recommend it : it does not fully support jdk 6 / ojdbc6.jar. For example the use of statement caching and jmx-support does not work with java 6 and throws exceptions. no internal statement cache - it relies on the jdbc driver's statement cache ( setPoolable() ) I submitted both issues to oracle