system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 506 Chapter 19. Client already acted this way. • Provide for forward compatibility with future minor protocol versions (Robert Haas, Badrul Chowdhury) Up to now, PostgreSQL servers simply rejected requests to use protocol versions

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication already acted this way. • Provide for forward compatibility with future minor protocol versions (Robert Haas, Badrul Chowd- hury) Up to now, PostgreSQL servers simply rejected requests to use protocol

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 490 Chapter 19. Client cases in practice. (CVE-2017-7484) • Fix possible corruption of “init forks” of unlogged indexes (Robert Haas, Michael Paquier) This could result in an unlogged index being set to an invalid state after

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication cases in practice. (CVE-2017-7484) • Fix possible corruption of “init forks” of unlogged indexes (Robert Haas, Michael Paquier) This could result in an unlogged index being set to an invalid state after

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 468 Chapter 19. Client version. • Fix psql’s tab completion logic to handle multibyte characters properly (Kyotaro Horiguchi, Robert Haas) • Fix psql’s tab completion for SECURITY LABEL (Tom Lane) Pressing TAB after SECURITY LABEL

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication version. • Fix psql’s tab completion logic to handle multibyte characters properly (Kyotaro Horiguchi, Robert Haas) • Fix psql’s tab completion for SECURITY LABEL (Tom Lane) Pressing TAB after SECURITY LABEL

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 476 Chapter 19. Client error (Álvaro Herrera) • Recursively fsync() the data directory after a crash (Abhijit Menon-Sen, Robert Haas) This ensures consistency if another crash occurs shortly later. (The second crash would have

system user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication error (Álvaro Herrera) • Recursively fsync() the data directory after a crash (Abhijit Menon-Sen, Robert Haas) This ensures consistency if another crash occurs shortly later. (The second crash would have

Unix user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication validator functions, if any. (CVE-2014-0061) • Avoid multiple name lookups during table and index DDL (Robert Haas, Andres Freund) If the name lookups come to different conclusions due to concurrent activity

Unix user name bryanh, ann, or robert would not be granted access. Unix user robert would only be allowed access when he tries to connect as PostgreSQL user bob, not as robert or anyone else. ann would only SYSTEM-USERNAME PG-USERNAME omicron bryanh bryanh omicron ann ann # bob has user name robert on these machines omicron robert bob # bryanh can also connect as guest1 omicron bryanh guest1 19.3. Authentication validator functions, if any. (CVE-2014-0061) • Avoid multiple name lookups during table and index DDL (Robert Haas, Andres Freund) If the name lookups come to different conclusions due to concurrent activity