如：  一键式集群安装部署初始化命令  Master 和 Standby 自动切换命令  更灵活的并行数据库备份恢复命令  高速 DDL 备份命令  并行 DDL 恢复命令  更先进的跨集群数据同步命令  集群间的表结构差异增量比对命令  良好兼容的 pgAdminIII 客户端  改善的 gpexpand 具有权限查看 pg_authid 系统表的用户都可以看到加密后的密码，不过这些密码都是 经过 MD5 加密后的字符串，由于 MD5 加密算法的不可逆性，查看者无法看到真实的原 始明文密码。当进行 DDL 的备份和恢复时，操作的是加密后的字符串，无法获取真实 的明文密码串。在设置密码的时候，密码就被加密了： =# CREATE USER name WITH ENCRYPTED PASSWORD 是编者自己修改编译的版本，不再是网上直接找到的版 本，目前已经针对 6 版本完成了必要的适配和优化，同时支持 4 版本和 5 版本，能够 正确的显示资源组和资源队列的信息，修复了资源队列刷新的 BUG，外部表的 DDL 信 息正确显示，物化视图，数据表的 UNLOGGED 属性等正确显示，表空间定义的正确显 示，数据库中的对象都按照登录角色的权限只显示应该看得到的对象，包括字段权限。 不过，编者在 github

= '< %m >' # special values: #log_statement = 'none' # none, ddl, mod, all #log_statement_stats = off #session_preload_libraries = '' 2018年PostgreSQL中国技术大会 微信号：laohouzi999 2018年PostgreSQL中国技术大会 微信号：laohouzi999 log_statement = 'none' # 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。

Ullman/Jennifer Widom《数据库系统实现》 查询编译器/ 优化器 事务管理器 DDL编译器 执行引擎 日志和恢复 并发控制 索引/文件/ 记录管理器 缓冲区管理器 缓冲区 锁表 存储管理器 存储 查询计划 对索引、文件和 记录的请求 页命令 事务命令 查询、更新 用户/ 应用 DDL命令 数据库管理员 数据、元数据、索引 日志页 读、写页 元数据、 统计数据

integer data type. This simplifies the creation of sequences matching the range of base columns. Some DDL commands now accept the current user (CURRENT_USER) or the session user (SESSION_USER) in place of row-level updates. Note Greenplum Database assigns XID values only to transactions that involve DDL or DML operations, which are typically the only transactions that require an XID. VMware Greenplum Simple MVCC Example Note Greenplum Database assigns XID values only to transactions that involve DDL or DML operations, which are typically the only transactions that require an XID. VMware Greenplum

problem could cause errors such as lock lock_name on object object_identifier is already held. 30557 - DDL : When performing a data reorganization with the ALTER TABLE command on a leaf partition of a partitioned this set. This has now been fixed and ORCA no longer falls back for such queries. 30334 - Storage: DDL : A system panic could occur if ALTER TABLE was used to add a new partition, and WITH (OIDS=FALSE) Greenplum Database 6 removes the RECHECK option from ALTER OPERATOR FAMILY and CREATE OPERATOR CLASS DDL (PostgreSQL 8.4). Greenplum now determines whether an index operator is “lossy” on-the-fly at runtime

problem could cause errors such as lock lock_name on object object_identifier is already held. 30557 - DDL : When performing a data reorganization with the ALTER TABLE command on a leaf partition of a partitioned this set. This has now been fixed and ORCA no longer falls back for such queries. 30334 - Storage: DDL : A system panic could occur if ALTER TABLE was used to add a new partition, and WITH (OIDS=FALSE) Greenplum Database 6 removes the RECHECK option from ALTER OPERATOR FAMILY and CREATE OPERATOR CLASS DDL (PostgreSQL 8.4). Greenplum now determines whether an index operator is “lossy” on-the-fly at runtime

problem could cause errors such as lock lock_name on object object_identifier is already held. 30557 - DDL : When performing a data reorganization with the ALTER TABLE command on a leaf partition of a partitioned this set. This has now been fixed and ORCA no longer falls back for such queries. 30334 - Storage: DDL : A system panic could occur if ALTER TABLE was used to add a new partition, and WITH (OIDS=FALSE) Greenplum Database 6 removes the RECHECK option from ALTER OPERATOR FAMILY and CREATE OPERATOR CLASS DDL (PostgreSQL 8.4). Greenplum now determines whether an index operator is “lossy” on-the-fly at runtime

the undocumented server configuration parameter allow_system_table_mods could have a value of none, ddl, dml, or all. In Greenplum 6, this parameter has changed to a Boolean value, with a default value spread between the segments based on the distribution policy that is defined for the table in the DDL at the time the table is created. When segment mirroring is enabled, for each segment instance there backup sets for Greenplum Database. By default, gpbackup stores only the object metadata files and DDL files for a backup in the Greenplum Database master data directory. Greenplum Database segments use

issues. 32683 Resolves an issue where minirepro diagnostic tool did not collect view statistics nor DDL when the query contained an EXPLAIN command. MADlib 32672 The database hung for a period of time problem could cause errors such as lock lock_name on object object_identifier is already held. 30557 - DDL Note If you have existing PXF external tables that specify a Hive* profile, you may be required this set. This has now been fixed and ORCA no longer falls back for such queries. 30334 - Storage: DDL A system panic could occur if ALTER TABLE was used to add a new partition, and WITH (OIDS=FALSE)

issues. 32683 Resolves an issue where minirepro diagnostic tool did not collect view statistics nor DDL when the query contained an EXPLAIN command. MADlib 32672 Resolves an issue where the database problem could cause errors such as lock lock_name on object object_identifier is already held. 30557 - DDL When performing a data reorganization with the ALTER TABLE command on a leaf partition of a partitioned this set. This has now been fixed and ORCA no longer falls back for such queries. 30334 - Storage: DDL A system panic could occur if ALTER TABLE was used to add a new partition, and WITH (OIDS=FALSE)