PostgreSQL数据库的物理存储结构主要是指硬盘上存储的文件，包括：数据文件、日志文件、参数文件、控制文件、WAL预写日志文件等等。
下面重点讨论一下PostgreSQL的控制文件。
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| 点击这里查看视频讲解：【赵渝强老师】PostgreSQL的控制文件 |
控制文件记录了数据库运行时的一些信息，比如数据库oid、是否是打开状态、WAL的位置、检查点的信息等等。PostgreSQL的控制文件是很重要的数据库文件。控制文件默认保存在$PGDATA/global/pg_control目录下，可以使用命令bin/pg_controldata查看控制文件的内容，具体的操作步骤如下：
（1）进入PostgreSQL的安装目录。
cd /home/postgres/training/pgsql
（2）执行命令查看控制文件的内容。
[postgres@mydb pgsql]$ bin/pg_controldata data/# 输出的信息如下：
pg_control version number: 1300
Catalog version number: 202007201
Database system identifier: 7208875389865427015
Database cluster state: in production
pg_control last modified: Fri 21 Apr 2023 05:56:43 PM CST
Latest checkpoint location: 0/2000098
Latest checkpoint's REDO location: 0/2000060
Latest checkpoint's REDO WAL file: 000000010000000000000002
Latest checkpoint's TimeLineID: 1
Latest checkpoint's PrevTimeLineID: 1
Latest checkpoint's full_page_writes: on
Latest checkpoint's NextXID: 0:492
Latest checkpoint's NextOID: 24576
Latest checkpoint's NextMultiXactId: 1
Latest checkpoint's NextMultiOffset: 0
Latest checkpoint's oldestXID: 478
Latest checkpoint's oldestXID's DB: 1
Latest checkpoint's oldestActiveXID: 492
Latest checkpoint's oldestMultiXid: 1
Latest checkpoint's oldestMulti's DB: 1
Latest checkpoint's oldestCommitTsXid:0
Latest checkpoint's newestCommitTsXid:0
Time of latest checkpoint: Fri 21 Apr 2023 05:56:43 PM CST
Fake LSN counter for unlogged rels: 0/3E8
Minimum recovery ending location: 0/0
Min recovery ending loc's timeline: 0
Backup start location: 0/0
Backup end location: 0/0
End-of-backup record required: no
wal_level setting: replica
wal_log_hints setting: off
max_connections setting: 100
max_worker_processes setting: 8
max_wal_senders setting: 10
max_prepared_xacts setting: 0
max_locks_per_xact setting: 64
track_commit_timestamp setting: off
Maximum data alignment: 8
Database block size: 8192
Blocks per segment of large relation: 131072
WAL block size: 8192
Bytes per WAL segment: 16777216
Maximum length of identifiers: 64
Maximum columns in an index: 32
Maximum size of a TOAST chunk: 1996
Size of a large-object chunk: 2048
Date/time type storage: 64-bit integers
Float8 argument passing: by value
Data page checksum version: 0
Mock authentication nonce:
7fda27a3058cbfb6cde2be36c58d96a33787abb79d40f4c07d36b932460def9b