日志

 本地日志

配置文件postgresql.conf

#------------------------------------------------------------------------------
# ERROR REPORTING AND LOGGING
#------------------------------------------------------------------------------

# - Where to Log -

#log_destination = 'stderr'        # Valid values are combinations of    # stderr, csvlog, syslog, and eventlog四选一，默认stderr
                    # stderr, csvlog, syslog, and eventlog,           # 也可以使用csvlog，这样输出的就是一个csv文件，这个好处是
                    # depending on platform.  csvlog                  # csv文件可以作为外表表导入数据库进行检索
                    # requires logging_collector to be on.            # 这个参数有效的前提是logging_collector也必须打开为on

# This is used when logging to stderr:
logging_collector = on        # Enable capturing of stderr and csvlog   #这个参数为on时，pg数据库就开始记录日志了，但是默认为off
                    # into log files. Required to be on for           #这个参数更改后需要restart数据库
                    # csvlogs.
                    # (change requires restart)

# These are only used if logging_collector is on:
log_directory = 'pg_log'        # directory where log files are written, # 该参数是配置日志的目录，可以是绝对目录，也可以是相对目录
                    # can be absolute or relative to PGDATA              # 相对目录要设置PGDATA的值，如果pg_log文件夹不存在要新建
log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log'    # log file name pattern, # 该参数是配置log的名字，一般用这个就行了，不用修改
                    # can include strftime() escapes
#log_file_mode = 0600            # creation mode for log files,           # 日志文件的权限，默认是600也不用更改
                    # begin with 0 to use octal notation
#log_truncate_on_rotation = off        # If on, an existing log file with the # 这个参数没必要开启，因为如果出现同名的日志文件，开启会
                    # same name as the new log file will be                # 清空原来日志，而不是在原来的基础上增加。但是在有一种情况
                    # truncated rather than appended to.                   # 下，可以设置为on，就是日志文件以星期格式命名，一周一轮回
                    # But such truncation only occurs on                   # 默认就保留了7天日志，这个是一个巧妙的日志处理方法。
                    # time-driven rotation, not on restarts
                    # or size-driven rotation.  Default is
                    # off, meaning append to existing files
                    # in all cases.
#log_rotation_age = 1d            # Automatic rotation of logfiles will     # 单个日志的生存期，默认为1天，在日志文件没有达到log_rotation_size
                    # happen after that time.  0 disables.                # 时，一天只生成一个日志文件
#log_rotation_size = 10MB        # Automatic rotation of logfiles will     # 单个日志文件大小，如果时间没有超过log_rotation_age，一个日志
                    # happen after that much log output.                  # 文件最大只能是10M，否则生成一个新的日志文件
                    # 0 disables.

# These are relevant when logging to syslog:
#syslog_facility = 'LOCAL0'                                             #这几个参数是在上面的log_destination设置为syslog需要配置的，很少用
#syslog_ident = 'postgres'
#syslog_sequence_numbers = on
#syslog_split_messages = on

# This is only relevant when logging to eventlog (win32):               # 这几个参数是在上面的log_destination设置为eventlog需要配置的，很少用
# (change requires restart)
#event_source = 'PostgreSQL'

# - When to Log -

#log_min_messages = warning        # values in order of decreasing detail:  # 控制写到服务器日志里的信息的详细程度。有效值是DEBUG5， DEBUG4， 
                    #   debug5                                           # DEBUG3，DEBUG2，DEBUG1， INFO，NOTICE，WARNING， ERROR，LOG
                    #   debug4                                           # FATAL， and PANIC。每个级别都包含它后面的级别。越靠后的数值 
                    #   debug3                                           # 发往服务器日志的信息越少，缺省是WARNING。
                    #   debug2
                    #   debug1
                    #   info
                    #   notice
                    #   warning
                    #   error
                    #   log
                    #   fatal
                    #   panic

#log_min_error_statement = error    # values in order of decreasing detail:
                    #   debug5                                           # 控制是否在服务器日志里输出那些导致错误条件的 SQL 语句。
                    #   debug4                                           # 所有导致一个特定级别(或者更高级别)错误的 SQL 语句都要
                    #   debug3                                           # 被记录。有效的值有DEBUG5， DEBUG4，DEBUG3， 
                    #   debug2                                           # DEBUG2，DEBUG1，INFO，NOTICE，WARNING，ERROR，LOG，FATAL
                    #   debug1                                           # ，和PANIC。缺省是ERROR，表示所有导致错误、致命错误、恐慌的
                    #   info                                             # SQL语句都将被记录。
                    #   notice
                    #   warning
                    #   error
                    #   log
                    #   fatal
                    #   panic (effectively off)

log_min_duration_statement = 0    # -1 is disabled, 0 logs all statements  # 这个参数非常重要，是排查慢查询的好工具，-1是关闭记录这类日志
                    # and their durations, > 0 logs only                 # 0 是记录所有的查询SQL，如果设置为大于0（毫秒），则超过该值的
                    # statements running at least this number            # 执行时间的sql会记录下来
                    # of milliseconds


# - What to Log -

#debug_print_parse = off                                                 # 调试类的，没必要打开该类日志
#debug_print_rewritten = off
#debug_print_plan = off
#debug_pretty_print = on
#log_checkpoints = off                                                   # 记录发生检查点的日志
#log_connections = off                                                   # 记录客户连接的日志
#log_disconnections = off                                                # 记录客户断开的日志
#log_duration = off                                                      # 记录每条SQL语句执行完成消耗的时间，将此配置设置为on,用于统计
                                                                         # 哪些SQL语句耗时较长。一般用上面那个log_min_duration_statement即可
#log_error_verbosity = default        # terse, default, or verbose messages
#log_hostname = on
log_line_prefix = '%m %p %u %d %r %e'            # special values:            # 日志输出格式（%m,%p实际意义配置文件中有解释）,可根据自己需要设置
                    #   %a = application name                            # （能够记录时间，用户名称，数据库名称，客户端IP和端口，sql语句方便定位问题）
                    #   %u = user name
                    #   %d = database name
                    #   %r = remote host and port
                    #   %h = remote host
                    #   %p = process ID
                    #   %t = timestamp without milliseconds
                    #   %m = timestamp with milliseconds
                    #   %n = timestamp with milliseconds (as a Unix epoch)
                    #   %i = command tag
                    #   %e = SQL state
                    #   %c = session ID
                    #   %l = session line number
                    #   %s = session start timestamp
                    #   %v = virtual transaction ID
                    #   %x = transaction ID (0 if none)
                    #   %q = stop here in non-session
                    #        processes
                    #   %% = '%'
                    # e.g. '<%u%%%d> '
#log_lock_waits = off            # log lock waits >= deadlock_timeout   # 控制当一个会话等待时间超过deadlock_timeout而被锁时是否产生一个
                                                                       # 日志信息。在判断一个锁等待是否会影响性能时是有用的，缺省是off。
#log_statement = 'none'            # none, ddl, mod, all                  # none, ddl, mod, all ---- 控制记录哪些SQL语句。
                                                                       # none不记录，ddl记录所有数据定义命令，比如CREATE,ALTER,和DROP语句。
                                                                       # mod记录所有ddl语句,加上数据修改语句INSERT,UPDATE等,all记录所有执行的语句，
                                                                       # 将此配置设置为all可跟踪整个数据库执行的SQL语句。
#log_replication_commands = off
#log_temp_files = -1            # log temporary files equal or larger
                    # than the specified size in kilobytes;
                    # -1 disables, 0 logs all temp files
log_timezone = 'PRC'                                                   # 日志时区，最好和服务器设置同一个时区，方便问题定位


# - Process Title -

#cluster_name = ''            # added to process titles if nonempty
                    # (change requires restart)
#update_process_title = on

 参考：https://www.cnblogs.com/easonbook/p/11983534.html

查询正在执行的sql

SELECT 
procpid, 
start, 
now() - start AS lap, 
current_query 
FROM 
(SELECT 
backendid, 
pg_stat_get_backend_pid(S.backendid) AS procpid, 
pg_stat_get_backend_activity_start(S.backendid) AS start, 
pg_stat_get_backend_activity(S.backendid) AS current_query 
FROM 
(SELECT pg_stat_get_backend_idset() AS backendid) AS S 
) AS S 
WHERE 
current_query <> '<IDLE>' 
ORDER BY 
lap DESC; 

　　

查看数据库目前是否有锁

-- 查看当前事务锁等待、持锁信息的SQL
with    
t_wait as    
(    
  select a.mode,a.locktype,a.database,a.relation,a.page,a.tuple,a.classid,a.granted,   
  a.objid,a.objsubid,a.pid,a.virtualtransaction,a.virtualxid,a.transactionid,a.fastpath,    
  b.state,b.query,b.xact_start,b.query_start,b.usename,b.datname,b.client_addr,b.client_port,b.application_name   
    from pg_locks a,pg_stat_activity b where a.pid=b.pid and not a.granted   
),   
t_run as   
(   
  select a.mode,a.locktype,a.database,a.relation,a.page,a.tuple,a.classid,a.granted,   
  a.objid,a.objsubid,a.pid,a.virtualtransaction,a.virtualxid,a.transactionid,a.fastpath,   
  b.state,b.query,b.xact_start,b.query_start,b.usename,b.datname,b.client_addr,b.client_port,b.application_name   
    from pg_locks a,pg_stat_activity b where a.pid=b.pid and a.granted   
),   
t_overlap as   
(   
  select r.* from t_wait w join t_run r on   
  (   
    r.locktype is not distinct from w.locktype and   
    r.database is not distinct from w.database and   
    r.relation is not distinct from w.relation and   
    r.page is not distinct from w.page and   
    r.tuple is not distinct from w.tuple and   
    r.virtualxid is not distinct from w.virtualxid and   
    r.transactionid is not distinct from w.transactionid and   
    r.classid is not distinct from w.classid and   
    r.objid is not distinct from w.objid and   
    r.objsubid is not distinct from w.objsubid and   
    r.pid <> w.pid   
  )    
),    
t_unionall as    
(    
  select r.* from t_overlap r    
  union all    
  select w.* from t_wait w    
)    
select locktype,datname,relation::regclass,page,tuple,virtualxid,transactionid::text,classid::regclass,objid,objsubid,   
string_agg(   
'Pid: '||case when pid is null then 'NULL' else pid::text end||chr(10)||   
'Lock_Granted: '||case when granted is null then 'NULL' else granted::text end||' , Mode: '||case when mode is null then 'NULL' else mode::text end||' , FastPath: '||case when fastpath is null then 'NULL' else fastpath::text end||' , VirtualTransaction: '||case when virtualtransaction is null then 'NULL' else virtualtransaction::text end||' , Session_State: '||case when state is null then 'NULL' else state::text end||chr(10)||   
'Username: '||case when usename is null then 'NULL' else usename::text end||' , Database: '||case when datname is null then 'NULL' else datname::text end||' , Client_Addr: '||case when client_addr is null then 'NULL' else client_addr::text end||' , Client_Port: '||case when client_port is null then 'NULL' else client_port::text end||' , Application_Name: '||case when application_name is null then 'NULL' else application_name::text end||chr(10)||    
'Xact_Start: '||case when xact_start is null then 'NULL' else xact_start::text end||' , Query_Start: '||case when query_start is null then 'NULL' else query_start::text end||' , Xact_Elapse: '||case when (now()-xact_start) is null then 'NULL' else (now()-xact_start)::text end||' , Query_Elapse: '||case when (now()-query_start) is null then 'NULL' else (now()-query_start)::text end||chr(10)||    
'SQL (Current SQL in Transaction): '||chr(10)||  
case when query is null then 'NULL' else query::text end,    
chr(10)||'--------'||chr(10)    
order by    
  (  case mode    
    when 'INVALID' then 0   
    when 'AccessShareLock' then 1   
    when 'RowShareLock' then 2   
    when 'RowExclusiveLock' then 3   
    when 'ShareUpdateExclusiveLock' then 4   
    when 'ShareLock' then 5   
    when 'ShareRowExclusiveLock' then 6   
    when 'ExclusiveLock' then 7   
    when 'AccessExclusiveLock' then 8   
    else 0   
  end  ) desc,   
  (case when granted then 0 else 1 end)  
) as lock_conflict  
from t_unionall   
group by   
locktype,datname,relation,page,tuple,virtualxid,transactionid::text,classid,objid,objsubid ;