0000000100000002000000D4的文件存储。 00000001 00000002 000000D4 timeline LogId LogSeg • WAL 日志文件XLOG 文件是一个逻辑概念，每一个XLOG文件， 大小为4G(16*256) ，由256个segment组成； 2016Postgres中国用户大会 Postgres Conference China 2016 中国用户大会  Locks of WAL • WALWriteLock 此锁用于将事务日志缓冲区数据写入WAL文件。 在采取这个锁定之后，所有的事务日志缓冲区数据到达预定点将被 刷新。 事务日志的刷新可能是由于提交，刷新数据缓冲区，截断提交日志 等。 在Xlog的切换期间。 在获取新

App检索的时，把非结构化数据通过 特征提取服务接口提取出向量，同时调用 AnalyticDB for PG的查询分析接口做查询。 特点： • 易用，结构化和非结构化数据关联查询。 • 准确性高，阿里自研向量检索算法。 Web APP AnalyticDB for PostgreSQL AnalyticDB for PostgreSQL Client 特征提取服 务 5.检索分析 1

h�ps://download.postgresql.org/pub/repos/yum/reporpms/EL-8-x86_64/pgdg-redhat- repo-latest.noarch.rpm #或者直接创建repo文件，内容如下 [pgdg13] name=PostgreSQL 13 for RHEL / Rocky $releasever - $basearch baseurl=h�ps://download.postgresql #将原数据目录下所有内容移动到新 数据目录下 # vi /usr/lib/systemd/system/postgresql-13.service #pg-13版本，修改systemd服 务文件，指定数据目录 #修改这行：Environment=PGDATA=/var/lib/pgsql/13/data/ 改为新的路径，如 下： Environment=PGDATA=/data_pg/data/ #将原数据目录下所有内容移动到新数 据目录下 # vi /usr/lib/systemd/system/postgresql.service #pg-10版本，修改systemd服务 文件，指定数据目录 #修改这行：Environment=PGDATA=/var/lib/pgsql/data/ 改为新的路径，如下： Environment=PGDATA=/data_pg/data/

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone's advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone's advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone's advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone's advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone’s advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note: In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone’s advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all de- tails are logged. Note: In case of fatal errors, the error message reported by the client

bug reports that can be handled in an effective fashion. No one is required to follow them but doing so tends to be to everyone’s advantage. We cannot promise to fix every bug right away. If the bug is If the program terminates with an operating system error, say which. If nothing at all happens, say so. Even if the result of your test case is a program crash or otherwise obvious it might not happen on extracting the message from the server log, set the run-time parameter log_error_verbosity to verbose so that all details are logged. Note: In case of fatal errors, the error message reported by the client