1.检查应用连接数
以管理员用户 gbase，登录数据库主节点。
接数据库，并执行如下 SQL 语句查看连接数。
SELECT count(*) FROM (SELECT pg_stat_get_backend_idset() AS backendid) AS s;
2.查看空闲连接
查看空闲(state 字段为”idle”)且长时间没有更新过的连接信息，使用如下命令。
SELECT * FROM pg_stat_activity where state='idle' order by state_change;
3.查看慢SQL
查看数据库实例中慢SQL语句执行信息，语法格式:
select * from dbe_perf.get_global_slow_sql_by_timestamp(start_timestamp, end_timestamp);
例如
select * from DBE_PERF.get_global_full_sql_by_timestamp('2024-08-30 09:25:22', '2024-08-30 23:54:41');
4.查看历史SQL
查看当前主节点SQL语句执行信息
select * from statement_history;
表的结构为
postgres=# \d statement_history
Unlogged table "pg_catalog.statement_history"
Column | Type | Modifiers
----------------------+--------------------------+-----------
db_name | name |
schema_name | name |
origin_node | integer |
user_name | name |
application_name | text |
client_addr | text |
client_port | integer |
unique_query_id | bigint |
debug_query_id | bigint |
query | text |
start_time | timestamp with time zone |
finish_time | timestamp with time zone |
slow_sql_threshold | bigint |
transaction_id | bigint |
thread_id | bigint |
session_id | bigint |
n_soft_parse | bigint |
n_hard_parse | bigint |
query_plan | text |
n_returned_rows | bigint |
n_tuples_fetched | bigint |
n_tuples_returned | bigint |
n_tuples_inserted | bigint |
n_tuples_updated | bigint |
n_tuples_deleted | bigint |
n_blocks_fetched | bigint |
n_blocks_hit | bigint |
db_time | bigint |
cpu_time | bigint |
execution_time | bigint |
parse_time | bigint |
plan_time | bigint |
rewrite_time | bigint |
pl_execution_time | bigint |
pl_compilation_time | bigint |
data_io_time | bigint |
net_send_info | text |
net_recv_info | text |
net_stream_send_info | text |
net_stream_recv_info | text |
lock_count | bigint |
lock_time | bigint |
lock_wait_count | bigint |
lock_wait_time | bigint |
lock_max_count | bigint |
lwlock_count | bigint |
lwlock_wait_count | bigint |
lwlock_time | bigint |
lwlock_wait_time | bigint |
details | bytea |
is_slow_sql | boolean |
trace_id | text |
Indexes:
"statement_history_time_idx" btree (start_time, is_slow_sql) TABLESPACE pg_default
Replica Identity: NOTHING
备库
select * from dbe_perf.standby_statement_history(true, '2024-08-30 09:25:22', '2024-08-30 23:54:41');
5.数据库实例中SQL语句执行信息
查看数据库实例中SQL语句执行信息，语法格式:
select * from dbe_perf.get_global_full_sql_by_timestamp('2024-08-30 09:25:22', '2024-08-30 23:54:41');
6.执行加载配置文件命令
select pg_reload_cong();
