title: Weblogic JDBC datasource gives "No resources currently available in pool" with just 1 active connection
body: <p>I am using weblogic JDBC datasource and my DB is Oracle 10g, below is the configuration.</p>
  
  <p>It used to work fine but suddenly it started giving problem, please see below exception.</p>
  
  <blockquote>
    <p>Weblogic JDBC
    datasource,java.sql.SQLException:
    Cannot obtain XAConnection
    weblogic.common.resourcepool.ResourceLimitException:
    No resources currently available in
    pool </p>
  
  <pre><code>&lt;?xml version="1.0" encoding="UTF-8"?&gt; &lt;jdbc-data-source
  </code></pre>
    
    <p>xmlns="http://www.bea.com/ns/weblogic/90"
    xmlns:sec="http://www.bea.com/ns/weblogic/90/security"
    xmlns:wls="http://www.bea.com/ns/weblogic/90/security/wls"
    xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
    xsi:schemaLocation="http://www.bea.com/ns/weblogic/920
    <a href="http://www.bea.com/ns/weblogic/920.xsd" rel="nofollow noreferrer">http://www.bea.com/ns/weblogic/920.xsd</a>">
    XL-Reference-DS<br>
    
        jdbc:oracle:oci:@abc.COM
        oracle.jdbc.driver.OracleDriver
        
          
            user
            DEV_260908
          
          
            password
            password
           
          
            dll
            ocijdbc10
          
          
            protocol
            oci
           
          
            oracle.jdbc.V8Compatible
            true
          
          
            baseDriverClass
            oracle.jdbc.driver.OracleDriver
          
           <br>
    
        1
        100
        1
        true
        SQL SELECT 1 FROM DUAL<br>
    <br>
    
        DataJndi
        OnePhaseCommit
    
    </p>
  </blockquote>
  
  <p>This exception is coming on dev environment where connected user is only one.</p>
  
  <p>I know this is related to pool max size but I also suspect this could be due to Oracle, might be Oracle isn't able to create connections.</p>
  
  <p>My questions:</p>
  
  <ol>
  <li>Is there any debug/logging parameter to enable datasource logging so that I can check the number of connections acquired, released, and unused in logs?</li>
  <li>How can I check oracle connection limit for a particular user?</li>
  </ol>