Thursday, April 30, 2009

c3p0.properties


#c3p0.acquireIncrement
#Default: 3
#Determines how many connections at a time c3p0 will try to acquire
#when the pool is exhausted. [See "Basic Pool Configuration"]

c3p0.acquireRetryAttempts=3
#Default: 30
#Defines how many times c3p0 will try to acquire a new Connection
#from the database before giving up. If this value is less than or
#equal to zero, c3p0 will keep trying to fetch a Connection
#indefinitely. [See "Configuring Recovery From Database Outages"]

#c3p0.acquireRetryDelay
#Default: 1000
#Milliseconds, time c3p0 will wait between acquire attempts.
#[See "Configuring Recovery From Database Outages"]

#c3p0.autoCommitOnClose
#Default: false
#The JDBC spec is unforgivably silent on what should happen to
#unresolved, pending transactions on Connection close. C3P0's
#default policy is to rollback any uncommitted, pending work.
#(I think this is absolutely, undeniably the right policy, but
#there is no consensus among JDBC driver vendors.) Setting
#autoCommitOnClose to true causes uncommitted pending work to be
#committed, rather than rolled back on Connection close. [Note:
#Since the spec is absurdly unclear on this question, application
#authors who wish to avoid bugs and inconsistent behavior should
#ensure that all transactions are explicitly either committed or
#rolled-back before close is called.] [See "Configuring Unresolved
#Transaction Handling"]

#c3p0.automaticTestTable
#Default: null
#If provided, c3p0 will create an empty table of the specified name,
#and use queries against that table to test the Connection. If
#automaticTestTable is provided, c3p0 will generate its own test
#query, therefore any preferredTestQuery set will be ignored. You
#should not work with the named table after c3p0 creates it; it
#should be strictly for c3p0's use in testing your Connection. (If
#you define your own ConnectionTester, it must implement the
#QueryConnectionTester interface for this parameter to be useful.)
#[See "Configuring Connection Testing"]

#c3p0.breakAfterAcquireFailure
#Default: false
#If true, a pooled DataSource will declare itself broken and be
#permanently closed if a Connection cannot be obtained from the
#database after making acquireRetryAttempts to acquire one. If
#false, failure to obtain a Connection will cause all Threads
#waiting for the pool to acquire a Connection to throw an Exception,
#but the DataSource will remain valid, and will attempt to acquire
#again following a call to getConnection(). [See "Configuring
#Recovery From Database Outages"]

#c3p0.checkoutTimeout
#Default: 0
#The number of milliseconds a client calling getConnection() will
#wait for a Connection to be checked-in or acquired when the pool
#is exhausted. Zero means wait indefinitely. Setting any positive
#value will cause the getConnection() call to time-out and break
#with an SQLException after the specified number of milliseconds.

#c3p0.connectionTesterClassName
#Default: com.mchange.v2.c3p0.impl.DefaultConnectionTester
#The fully qualified class-name of an implememtation of the
#ConnectionTester interface, or QueryConnectionTester if you would
#like instances to have access to a user-configured preferredTestQuery.
#This can be used to customize how c3p0 DataSources test Connections,
#but with the introduction of automaticTestTable and preferredTestQuery
#configuration parameters, "rolling your own" should be overkill for
#most users. [See "Configuring Connection Testing"

#c3p0.factoryClassLocation
#Default: null
#DataSources that will be bound by JNDI and use that API's
#Referenceable interface to store themselves may specify a URL
#from which the class capable of dereferencing a them may be
#loaded. If (as is usually the case) the c3p0 libraries will
#be locally available to the JNDI service, leave this set as null.

#c3p0.forceIgnoreUnresolvedTransactions
#Default: false
#Strongly disrecommended. Setting this to true may lead to subtle
#and bizarre bugs. This is a terrible setting, leave it alone
#unless absolutely necessary. It is here to workaround broken
#databases / JDBC drivers that do not properly support transactions,
#but that allow Connections' autoCommit flags to go to false
#regardless. If you are using a database that supports transactions
#"partially" (this is oxymoronic, as the whole point of transactions
#is to perform operations reliably and completely, but nonetheless
#such databases are out there), if you feel comfortable ignoring the
#fact that Connections with autoCommit == false may be in the middle
#of transactions and may hold locks and other resources, you may
#turn off c3p0's wise default behavior, which is to protect itself,
#as well as the usability and consistency of the database, by either
#rolling back (default) or committing (see c3p0.autoCommitOnClose above)
#unresolved transactions. This should only be set to true when you
#are sure you are using a database that allows Connections'
#autoCommit flag to go to false, but offers no other meaningful
#support of transactions. Otherwise setting this to true is just
#a bad idea. [See "Configuring Unresolved Transaction Handling"]

#c3p0.idleConnectionTestPeriod=
#Default: 0
#If this is a number greater than 0, c3p0 will test all idle, pooled
#but unchecked-out connections, every this number of seconds.
#[See "Configuring Connection Testing"]

c3p0.initialPoolSize=10
#Default: 3
#Number of Connections a pool will try to acquire upon startup.
#Should be between minPoolSize and maxPoolSize. [See "Basic Pool
#Configuration"]

c3p0.maxIdleTime=600
#Default: 0
#Seconds a Connection can remain pooled but unused before being
#discarded. Zero means idle connections never expire. [See "Basic
#Pool Configuration"]

c3p0.maxPoolSize=128
#Default: 15
#Maximum number of Connections a pool will maintain at any given
#time. [See "Basic Pool Configuration"]

#c3p0.maxStatements
#Default: 0
#The size of c3p0's global PreparedStatement cache. If both
#maxStatements and maxStatementsPerConnection are zero, statement
#caching will not be enabled. If maxStatements is zero but
#maxStatementsPerConnection is a non-zero value, statement
#caching will be enabled, but no global limit will be enforced,
#only the per-connection maximum. maxStatements controls the total
#number of Statements cached, for all Connections. If set, it
#should be a fairly large number, as each pooled Connection
#requires its own, distinct flock of cached statements. As a
#guide, consider how many distinct PreparedStatements are used
#frequently in your application, and multiply that number by
#maxPoolSize to arrive at an appropriate value. Though maxStatements
#is the JDBC standard parameter for controlling statement caching,
#users may find c3p0's alternative maxStatementsPerConnection
#more intuitive to use. [See "Configuring Statement Pooling"]

#c3p0.maxStatementsPerConnection
#Default: 0
#The number of PreparedStatements c3p0 will cache for a single
#pooled Connection. If both maxStatements and
#maxStatementsPerConnection are zero, statement caching will
#not be enabled. If maxStatementsPerConnection is zero but
#maxStatements is a non-zero value, statement caching will be
#enabled, and a global limit enforced, but otherwise no limit
#will be set on the number of cached statements for a single
#Connection. If set, maxStatementsPerConnection should be set
#to about the number distinct PreparedStatements that are used
#frequently in your application, plus two or three extra so
#infrequently statements don't force the more common cached
#statements to be culled. Though maxStatements is the JDBC
#standard parameter for controlling statement caching, users
#may find maxStatementsPerConnection more intuitive to use.
#[See "Configuring Statement Pooling"]

c3p0.minPoolSize=5
#Default: 3
#Minimum number of Connections a pool will maintain at any
#given time. [See "Basic Pool Configuration"]

#c3p0.numHelperThreads
#Default: 3
#c3p0 is very asynchronous. Slow JDBC operations are generally
#performed by helper threads that don't hold contended locks.
#Spreading these operations over multiple threads can
#significantly improve performance by allowing multiple
#operations to be performed simultaneously.

#c3p0.preferredTestQuery
#Default: null
#Defines the query that will be executed for all connection
#tests, if the default ConnectionTester (or some other
#implementation of QueryConnectionTester) is being used.
#Defining a preferredTestQuery that will execute quickly
#in your database may dramatically speed up Connection tests.
#(If no preferredTestQuery is set, the default ConnectionTester
#executes a getTables() call on the Connection's
#DatabaseMetaData. Depending on your database, this may
#execute more slowly than a "normal" database query.) NOTE:
#The table against which your preferredTestQuery will be run
#must exist in the database schema prior to your initialization
#of your DataSource. If your application defines its own schema,
#try automaticTestTable instead. [See "Configuring Connection
#Testing"]

#c3p0.propertyCycle
#Default: 300
#Maximum time in seconds before user configuration constraints
#are enforced. c3p0 enforces configuration constraints continually,
#and ignores this parameter. It is included for JDBC 3 completeness.

#c3p0.testConnectionOnCheckin
#Default: false
#If true, an operation will be performed asynchronously at every
#connection checkin to verify that the connection is valid. Use
#in combination with idleConnectionTestPeriod for quite reliable,
#always asynchronous Connection testing. Also, setting an
#automaticTestTable or preferredTestQuery will usually speed
#up all connection tests. [See "Configuring Connection Testing"]

#c3p0.testConnectionOnCheckout
#Default: false
#Use only if necessary. Expensive. If true, an operation will
#be performed at every connection checkout to verify that the
#connection is valid. Better choice: verify connections periodically
#using idleConnectionTestPeriod. Also, setting an automaticTestTable
#or preferredTestQuery will usually speed up all connection tests.
#[See "Configuring Connection Testing"]

#c3p0.usesTraditionalReflectiveProxies
#Default: false
#c3p0 originally used reflective dynamic proxies for implementations
#of Connections and other JDBC interfaces. As of c3p0-0.8.5,
#non-reflective, code-generated implementations are used instead.
#As this was a major change, and the old codebase had been
#extensively used and tested, this parameter was added to allow
#users to revert of they had problems. The new, non-reflexive
#implementation is faster, and has now been widely deployed and
#tested, so it is unlikely that this parameter will be useful.
#Both the old reflective and newer non-reflective codebases are
#being maintained, but support for the older codebase may (or may not)
#be dropped in the future.

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