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See AlsoManual ChaptersPG18See Also INSERT, SELECTSee Also Seeking in a Large ObjectManual ChaptersPG1833.3.7. Seeking in a Large Object To change the current read or write location associated with a large object descriptor, call int lo_lseek(PGconn *conn, int fd, int offset, int whence); Thi…Seeking in a Large Object seg — a datatype for line segments or floating point intervalsManual ChaptersPG18F.39. seg — a datatype for line segments or floating point intervals This module implements a data type seg for representing line segments, or floating point intervals. seg can represent unc…seg — a datatype for line segments or floating point intervals SELECTManual ChaptersPG18SELECT SELECT, TABLE, WITH — retrieve rows from a table or view Synopsis [ WITH [ RECURSIVE ] with_query [, ...] ] SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ] [ { * | expression …SELECT SELECT in WITHManual ChaptersPG187.8.1. SELECT in WITH The basic value of SELECT in WITH is to break down complicated queries into simpler parts. An example is: WITH regional_sales AS ( SELECT region, SUM(amount) AS total_s…SELECT in WITH SELECT INTOManual ChaptersPG18SELECT INTO SELECT INTO — define a new table from the results of a query Synopsis [ WITH [ RECURSIVE ] with_query [, ...] ] SELECT [ ALL | DISTINCT [ ON ( expression [, ...] ) ] ] [ { * | ex…SELECT INTO SELECT ListManual ChaptersPG18SELECT List The SELECT list (between the key words SELECT and FROM) specifies expressions that form the output rows of the SELECT statement. The expressions can (and usually do) refer to col…SELECT List Select ListsManual ChaptersPG187.3. Select Lists As shown in the previous section, the table expression in the SELECT command constructs an intermediate virtual table by possibly combining tables, views, eliminating rows,…Select Lists SELECT Output ColumnsManual ChaptersPG1810.6. SELECT Output Columns The rules given in the preceding sections will result in assignment of non-unknown data types to all expressions in an SQL query, except for unspecified-type lite…SELECT Output Columns Select-List ItemsManual ChaptersPG187.3.1. Select-List Items The simplest kind of select list is * which emits all columns that the table expression produces. Otherwise, a select list is a comma-separated list of value express…Select-List Items Selecting LocalesManual ChaptersPG1823.1.3. Selecting Locales Locales can be selected in different scopes depending on requirements. The above overview showed how locales are specified using initdb to set the defaults for the …Selecting Locales Semi-Internal OptionsManual ChaptersPG18Semi-Internal Options The options described here are used mainly for debugging purposes, and in some cases to assist with recovery of severely damaged databases. There should be no reason to…Semi-Internal Options Sending ServersManual ChaptersPG1819.6.1. Sending Servers These parameters can be set on any server that is to send replication data to one or more standby servers. The primary is always a sending server, so these parameters…Sending Servers Sepgsql FunctionsManual ChaptersPG18F.40.6. Sepgsql Functions Table F.32 shows the available functions. Table F.32. Sepgsql Functions Function Description sepgsql_getcon () → text Returns the client domain, the current securit…Sepgsql Functions sepgsql — SELinux-, label-based mandatory access control (MAC) security moduleManual ChaptersPG18F.40. sepgsql — SELinux-, label-based mandatory access control (MAC) security module sepgsql is a loadable module that supports label-based mandatory access control (MAC) based on SELinux se…sepgsql — SELinux-, label-based mandatory access control (MAC) security module Sequence Manipulation FunctionsManual ChaptersPG189.17. Sequence Manipulation Functions This section describes functions for operating on sequence objects, also called sequence generators or just sequences. Sequence objects are special sing…Sequence Manipulation Functions sequencesManual ChaptersPG1835.47. sequences The view sequences contains all sequences defined in the current database. Only those sequences are shown that the current user has access to (by way of being the owner or h…sequences Serial TypesManual ChaptersPG188.1.4. Serial Types Note This section describes a PostgreSQL-specific way to create an autoincrementing column. Another way is to use the SQL-standard identity column feature, described at S…Serial Types Serializable Isolation LevelManual ChaptersPG1813.2.3. Serializable Isolation Level The Serializable isolation level provides the strictest transaction isolation. This level emulates serial transaction execution for all committed transac…Serializable Isolation Level Serialization Failure HandlingManual ChaptersPG1813.5. Serialization Failure Handling Both Repeatable Read and Serializable isolation levels can produce errors that are designed to prevent serialization anomalies. As previously stated, app…Serialization Failure Handling ServerManual ChaptersPG18E.6.3.1. ServerServer Server AdministrationManual ChaptersPG18Part III. Server Administration This part covers topics that are of interest to a PostgreSQL administrator. This includes installation, configuration of the server, management of users and d…Server Administration Server API and ABI Stability GuidanceManual ChaptersPG1836.10.6. Server API and ABI Stability Guidance This section contains guidance to authors of extensions and other server plugins about API and ABI stability in the PostgreSQL server.Server API and ABI Stability Guidance Server ApplicationsManual ChaptersPG18G.2. Server Applications Some applications run on the PostgreSQL server itself. Currently, no such applications are included in the contrib directory. See also PostgreSQL Server Applications…Server Applications Server ApplicationsManual ChaptersPG18E.6.3.7. Server Applications Change initdb to default to enabling checksums (Greg Sabino Mullane) § § The new initdb option --no-data-checksums disables checksums. Add initdb option --no-syn…Server Applications Server ConfigurationManual ChaptersPG18E.6.3.1.6. Server Configuration Add support for the OAuth authentication method (Jacob Champion, Daniel Gustafsson, Thomas Munro) § This adds an oauth authentication method to pg_hba.conf, l…Server Configuration Server ConfigurationManual ChaptersPG18Chapter 19. Server Configuration There are many configuration parameters that affect the behavior of the database system. In the first section of this chapter we describe how to interact wit…Server Configuration Server ProgrammingManual ChaptersPG18Part V. Server Programming This part is about extending the server functionality with user-defined functions, data types, triggers, etc. These are advanced topics which should be approached …Server Programming Server Programming InterfaceManual ChaptersPG18Chapter 45. Server Programming Interface The Server Programming Interface (SPI) gives writers of user-defined C functions the ability to run SQL commands inside their functions or procedures…Server Programming Interface Server Setup and OperationManual ChaptersPG18Chapter 18. Server Setup and Operation This chapter discusses how to set up and run the database server, and its interactions with the operating system. The directions in this chapter assume…Server Setup and Operation Server Signaling FunctionsManual ChaptersPG189.28.2. Server Signaling Functions The functions shown in Table 9.96 send control signals to other server processes. Use of these functions is restricted to superusers by default but access …Server Signaling Functions Server Start-up FailuresManual ChaptersPG1818.3.1. Server Start-up Failures There are several common reasons the server might fail to start. Check the server's log file, or start it by hand (without redirecting standard output or sta…Server Start-up Failures Server-Side FunctionsManual ChaptersPG1833.4. Server-Side Functions Server-side functions tailored for manipulating large objects from SQL are listed in Table 33.1. Table 33.1. SQL-Oriented Large Object Functions Function Descript…Server-Side Functions sess-keyManual ChaptersPG18F.26.3.8.6. sess-key Use separate session key. Public-key encryption always uses a separate session key; this option is for symmetric-key encryption, which by default uses the S2K key direct…sess-key Session Information FunctionsManual ChaptersPG189.27.1. Session Information Functions Table 9.71 shows several functions that extract session and system information. In addition to the functions listed in this section, there are a number …Session Information Functions SETManual ChaptersPG18SET SET — change a run-time parameter Synopsis SET [ SESSION | LOCAL ] configuration_parameter { TO | = } { value | 'value' | DEFAULT } SET [ SESSION | LOCAL ] TIME ZONE { value | 'value' | …SET SET AUTOCOMMITManual ChaptersPG18SET AUTOCOMMIT SET AUTOCOMMIT — set the autocommit behavior of the current session Synopsis SET AUTOCOMMIT { = | TO } { ON | OFF }SET AUTOCOMMIT SET CONNECTIONManual ChaptersPG18SET CONNECTION SET CONNECTION — select a database connection Synopsis SET CONNECTION [ TO | = ] connection_nameSET CONNECTION SET CONSTRAINTSManual ChaptersPG18SET CONSTRAINTS SET CONSTRAINTS — set constraint check timing for the current transaction Synopsis SET CONSTRAINTS { ALL | name [, ...] } { DEFERRED | IMMEDIATE }SET CONSTRAINTS SET DESCRIPTORManual ChaptersPG18SET DESCRIPTOR SET DESCRIPTOR — set information in an SQL descriptor area Synopsis SET DESCRIPTOR descriptor_name descriptor_header_item = value SET DESCRIPTOR descriptor_name VALUE number d…SET DESCRIPTOR