有幸遇到这个错误了， 12c的PGA_AGGREGATE_LIMIT 限制PGA功能还是有用的：
Exception in thread "main" java.sql.SQLException: ORA-04036: 实例使用的 PGA 内存超出 PGA_AGGREGATE_LIMIT
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:445)
at oracle.jdbc.driver.T4CTTIoer.processError(T4CTTIoer.java:396)
at oracle.jdbc.driver.T4C8Oall.processError(T4C8Oall.java:879)
at oracle.jdbc.driver.T4CTTIfun.receive(T4CTTIfun.java:450)
at oracle.jdbc.driver.T4CTTIfun.doRPC(T4CTTIfun.java:192)
at oracle.jdbc.driver.T4C8Oall.doOALL(T4C8Oall.java:531)
at oracle.jdbc.driver.T4CPreparedStatement.doOall8(T4CPreparedStatement.java:207)
oracle@localhost:/u01/app/oracle/diag/rdbms/cdb1/cdb1/trace$ oerr ora 4036
04036, 00000, "PGA memory used by the instance exceeds PGA_AGGREGATE_LIMIT"
// *Cause: Private memory across the instance exceeded the limit specified
// in the PGA_AGGREGATE_LIMIT initialization parameter. The largest
// sessions using Program Global Area (PGA) memory were interrupted
// to get under the limit.
// *Action: Increase the PGA_AGGREGATE_LIMIT initialization parameter or reduce
// memory usage.
pga_aggregate_limit
limit of aggregate PGA memory consumed by the instance