ORA00020

# ORA00020
## 线程数达到最大
```sql
SQL> ho oerr ora 00020
00020, 00000, "maximum number of processes (%s) exceeded"
// *Cause:  All process state objects are in use.
// *Action: Increase the value of the PROCESSES initialization parameter.
```

## 问题处理
所有的线程都处于活动状态，如果要处理问题需要增加线程数,增加后需要重启数据库。
```
SQL>  show parameter processes

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
aq_tm_processes                      integer     1
db_writer_processes                  integer     2
gcs_server_processes                 integer     0
global_txn_processes                 integer     1
job_queue_processes                  integer     1000
log_archive_max_processes            integer     4
processes                            integer     150
SQL> alter system set processes=1000 scope=spfile;

System altered.
SQL> create pfile from spfile;

File created.
SQL> shutdown immediate;
Database closed.
Database dismounted.
ORACLE instance shut down.

SQL> startup
ORACLE instance started.

Total System Global Area 1.1758E+10 bytes
Fixed Size                  2263936 bytes
Variable Size            2181039232 bytes
Database Buffers         9563013120 bytes
Redo Buffers               12103680 bytes
Database mounted.
Database opened.

SQL> show parameter processes

NAME                                 TYPE        VALUE
------------------------------------ ----------- ------------------------------
aq_tm_processes                      integer     1
db_writer_processes                  integer     2
gcs_server_processes                 integer     0
global_txn_processes                 integer     1
job_queue_processes                  integer     1000
log_archive_max_processes            integer     4
processes                            integer     1000

```