1PG_WALDUMP(1) PostgreSQL 11.3 Documentation PG_WALDUMP(1)
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6 pg_waldump - display a human-readable rendering of the write-ahead log
7 of a PostgreSQL database cluster
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10 pg_waldump [option...] [startseg [endseg]]
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13 pg_waldump displays the write-ahead log (WAL) and is mainly useful for
14 debugging or educational purposes.
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16 This utility can only be run by the user who installed the server,
17 because it requires read-only access to the data directory.
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20 The following command-line options control the location and format of
21 the output:
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23 startseg
24 Start reading at the specified log segment file. This implicitly
25 determines the path in which files will be searched for, and the
26 timeline to use.
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28 endseg
29 Stop after reading the specified log segment file.
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31 -b
32 --bkp-details
33 Output detailed information about backup blocks.
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35 -e end
36 --end=end
37 Stop reading at the specified WAL location, instead of reading to
38 the end of the log stream.
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40 -f
41 --follow
42 After reaching the end of valid WAL, keep polling once per second
43 for new WAL to appear.
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45 -n limit
46 --limit=limit
47 Display the specified number of records, then stop.
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49 -p path
50 --path=path
51 Specifies a directory to search for log segment files or a
52 directory with a pg_wal subdirectory that contains such files. The
53 default is to search in the current directory, the pg_wal
54 subdirectory of the current directory, and the pg_wal subdirectory
55 of PGDATA.
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57 -r rmgr
58 --rmgr=rmgr
59 Only display records generated by the specified resource manager.
60 If list is passed as name, print a list of valid resource manager
61 names, and exit.
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63 -s start
64 --start=start
65 WAL location at which to start reading. The default is to start
66 reading the first valid log record found in the earliest file
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69 -t timeline
70 --timeline=timeline
71 Timeline from which to read log records. The default is to use the
72 value in startseg, if that is specified; otherwise, the default is
73 1.
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75 -V
76 --version
77 Print the pg_waldump version and exit.
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79 -x xid
80 --xid=xid
81 Only display records marked with the given transaction ID.
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83 -z
84 --stats[=record]
85 Display summary statistics (number and size of records and
86 full-page images) instead of individual records. Optionally
87 generate statistics per-record instead of per-rmgr.
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89 -?
90 --help
91 Show help about pg_waldump command line arguments, and exit.
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94 Can give wrong results when the server is running.
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96 Only the specified timeline is displayed (or the default, if none is
97 specified). Records in other timelines are ignored.
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99 pg_waldump cannot read WAL files with suffix .partial. If those files
100 need to be read, .partial suffix needs to be removed from the file
101 name.
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104 Section 30.5
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108PostgreSQL 11.3 2019 PG_WALDUMP(1)