PoolLimitSQLException with temporary table [duplicate] - jdbc

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Closed 3 years ago.
I need to use a global temporary table as proxy to read a BLOB column from a database link in an application I've inherited. Using ON COMMIT DELETE ROWS I wasn't able to read my values back (as if every query was being ran in a different connection from pool) so I eventually settled with:
CREATE GLOBAL TEMPORARY TABLE TMP_FOO (
ID VARCHAR2(64 BYTE) NOT NULL ENABLE,
FOO BLOB NOT NULL ENABLE,
CONSTRAINT TMP_FOO_PK PRIMARY KEY (ID) ENABLE
) ON COMMIT PRESERVE ROWS;
While this works, I'm now repeatedly getting:
weblogic.jdbc.extensions.PoolLimitSQLException: weblogic.common.resourcepool.ResourceLimitException: No resources currently available in pool foods to allocate to applications, please increase the size of the pool and retry
WebLogic console certainly shows 15 active connections. But I am the only user!
What am I doing wrong that's preventing connections from being reused?
// Custom method that returns java.sql.Connection from javax.naming.InitialContext.lookup(String)
Connection conn = ds.getConnection();
PreparedStatement st = null;
ResultSet rs = null;
String sql;
Blob foo;
try {
sql = "INSERT INTO TMP_FOO (ID, FOO) SELECT ?, FOO FROM REMOTE_TABLE#DBLINK WHERE REMOTE_ID = ?";
st = conn.prepareStatement(sql);
st.setString(1, "Random UUID here");
st.setString(2, "20");
System.out.println("Rows inserted: " + st.executeUpdate());
sql = "SELECT FOO FROM TMP_FOO WHERE ID = ?";
st = conn.prepareStatement(sql);
st.setString(1, "Random UUID here");
rs = st.executeQuery();
if (!rs.next()) {
throw new RuntimeException("Not found");
}
foo = rs.getBlob("foo");
} catch(Exception e) {
// Final code will do something meaningful here
System.out.println("[ERROR] " + e.getMessage());
} finally {
conn.rollback();
}