分类目录归档：数据库

PostgreSQL目前配置中,不直接记录日志文件,这样的情况给数据库后期出现问题(特别是无法正常启动的情况)分析带来很大麻烦,不知道具体问题所在,建议在PG安装完成之后,启用日志功能,便于数据库运行状态检查和错误跟踪,主要日志参数涉及以下配置

log_destination = 'stderr'              # Valid values are combinations of
                                        # stderr, csvlog, jsonlog, syslog, and
                                        # eventlog, depending on platform.
                                        # csvlog and jsonlog require
                                        # logging_collector to be on.

# This is used when logging to stderr:
logging_collector = on          # Enable capturing of stderr, jsonlog,
                                        # and csvlog into log files. Required
                                        # to be on for csvlogs and jsonlogs.
                                        # (change requires restart)
//是否将日志重定向至文件中，默认是off。

# These are only used if logging_collector is on:
log_directory = 'pg_log'                   # directory where log files are written,
                                        # can be absolute or relative to PGDATA
//日志文件目录，默认是PGDATA的相对路径，即PGDATA的相对路径，即{PGDATA}/pg_log，也可以改为绝对路径。
//日志文件可能会非常多，建议将日志重定向到其他目录或分区。
//将此配置修改其他目录时，必须先创建此目录，并修改权限，使得postgres用户对该目录有写权限。

log_filename = 'postgresql-%Y-%m-%d_%H%M%S.log' # log file name pattern,
                                        # can include strftime() escapes
log_file_mode = 0600                    # creation mode for log files,
                                        # begin with 0 to use octal notation
log_rotation_age = 1d                   # Automatic rotation of logfiles will
                                        # happen after that time.  0 disables.
log_rotation_size = 10MB                # Automatic rotation of logfiles will
                                        # happen after that much log output.
                                        # 0 disables.
#log_truncate_on_rotation = off         # If on, an existing log file with the
                                        # same name as the new log file will be
                                        # truncated rather than appended to.
                                        # But such truncation only occurs on
                                        # time-driven rotation, not on restarts
                                        # or size-driven rotation.  Default is
                                        # off, meaning append to existing files
                                        # in all cases.
//当日志文件已存在时，该配置如果为off，新生成的日志将在文件尾部追加，如果为on，则会覆盖原来的日志。

上述配置得到的结果如下

[postgres@xifenfei pg_log]$ pwd
/data/pg/15/data/pg_log
[postgres@xifenfei pg_log]$ ls -l
total 4
-rw------- 1 postgres postgres 1263 Apr  3 22:37 postgresql-2025-04-03_223117.log