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DescriptionManual ChaptersPG18Description SECURITY LABEL applies a security label to a database object. An arbitrary number of security labels, one per label provider, can be associated with a given database object. Labe…Description DescriptionManual ChaptersPG18Description SELECT retrieves rows from zero or more tables. The general processing of SELECT is as follows: All queries in the WITH list are computed. These effectively serve as temporary ta…Description DescriptionManual ChaptersPG18Description SELECT INTO creates a new table and fills it with data computed by a query. The data is not returned to the client, as it is with a normal SELECT. The new table's columns have th…Description DescriptionManual ChaptersPG18Description SET CONSTRAINTS sets the behavior of constraint checking within the current transaction. IMMEDIATE constraints are checked at the end of each statement. DEFERRED constraints are …Description DescriptionManual ChaptersPG18Description This command sets the current user identifier of the current SQL session to be role_name. The role name can be written as either an identifier or a string literal. After SET ROLE…Description DescriptionManual ChaptersPG18Description This command sets the session user identifier and the current user identifier of the current SQL session to be user_name. The user name can be written as either an identifier or …Description DescriptionManual ChaptersPG18Description The SET TRANSACTION command sets the characteristics of the current transaction. It has no effect on any subsequent transactions. SET SESSION CHARACTERISTICS sets the default tra…Description DescriptionManual ChaptersPG18Description The SET command changes run-time configuration parameters. Many of the run-time parameters listed in Chapter 19 can be changed on-the-fly with SET. (Some parameters can only be c…Description DescriptionManual ChaptersPG18Description SHOW will display the current setting of run-time parameters. These variables can be set using the SET statement, by editing the postgresql.conf configuration file, through the P…Description DescriptionManual ChaptersPG18Description This command begins a new transaction block. If the isolation level, read/write mode, or deferrable mode is specified, the new transaction has those characteristics, as if SET TR…Description DescriptionManual ChaptersPG18Description TRUNCATE quickly removes all rows from a set of tables. It has the same effect as an unqualified DELETE on each table, but since it does not actually scan the tables it is faster…Description DescriptionManual ChaptersPG18Description UNLISTEN is used to remove an existing registration for NOTIFY events. UNLISTEN cancels any existing registration of the current PostgreSQL session as a listener on the notificat…Description DescriptionManual ChaptersPG18Description UPDATE changes the values of the specified columns in all rows that satisfy the condition. Only the columns to be modified need be mentioned in the SET clause; columns not explic…Description DescriptionManual ChaptersPG18Description VACUUM reclaims storage occupied by dead tuples. In normal PostgreSQL operation, tuples that are deleted or obsoleted by an update are not physically removed from their table; th…Description DescriptionManual ChaptersPG18Description VALUES computes a row value or set of row values specified by value expressions. It is most commonly used to generate a “constant table” within a larger command, but it can be us…Description DescriptionManual ChaptersPG18Description vacuumlo is a simple utility program that will remove any “orphaned” large objects from a PostgreSQL database. An orphaned large object (LO) is considered to be any LO whose OID …Description Description of FunctionsManual ChaptersPG18F.50.2. Description of Functions Table F.37 shows the functions provided by this module. These functions provide straightforward XML parsing and XPath queries. Table F.37. xml2 Functions Fun…Description of Functions Designing JSON DocumentsManual ChaptersPG188.14.2. Designing JSON Documents Representing data as JSON can be considerably more flexible than the traditional relational data model, which is compelling in environments where requirement…Designing JSON Documents Destroying a DatabaseManual ChaptersPG1822.5. Destroying a Database Databases are destroyed with the command DROP DATABASE: DROP DATABASE name; Only the owner of the database, or a superuser, can drop a database. Dropping a databa…Destroying a Database Detection by configureManual ChaptersPG18J.2.5. Detection by configure Before you can build the documentation you need to run the configure script, as you would when building the PostgreSQL programs themselves. Check the output nea…Detection by configure Determining Disk UsageManual ChaptersPG1827.6.1. Determining Disk Usage Each table has a primary heap disk file where most of the data is stored. If the table has any columns with potentially-wide values, there also might be a TOAS…Determining Disk Usage dev@tienlen_validationExtensionsExtensionsTien Len validation functions for game server database.dev tle dev@tienlen_validation Functions and aggregatesFunctions and aggregates · Extensions Developer OptionsManual ChaptersPG1817.3.3.6. Developer Options Most of the options in this section are only of interest for developing or debugging PostgreSQL. They are not recommended for production builds, except for --enab…Developer Options Developer OptionsManual ChaptersPG1817.4.3.7. Developer Options Most of the options in this section are only of interest for developing or debugging PostgreSQL. They are not recommended for production builds, except for --debu…Developer Options Developer OptionsManual ChaptersPG1819.17. Developer Options The following parameters are intended for developer testing, and should never be used on a production database. However, some of them can be used to assist with the …Developer Options Developer TargetsManual ChaptersPG1817.4.4.2. Developer Targets reformat-dat-files # Rewrite catalog data files into standard format expand-dat-files # Expand all data files to include defaults update-unicode # Update unicode …Developer Targets Deviations from the SQL StandardManual ChaptersPG189.16.2.1. Deviations from the SQL Standard PostgreSQL's implementation of the SQL/JSON path language has the following deviations from the SQL/JSON standard.Deviations from the SQL Standard device_typeExtensionsExtensionsFixed-byte enum-like data type for mobile device types with comparison operators and btree/hash operator classes. data-type enum mobile pg_device_type Data typesData types · Extensions diag_plannerExtensionsExtensionsincubator repositries diag_planner MonitoringMonitoring · Extensions DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see CLUSTER and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any default …Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see CREATE DATABASE and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any …Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see CREATE ROLE and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any defa…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see DROP DATABASE and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any de…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see DROP ROLE and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any defaul…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics pg_dump internally executes SELECT statements. If you have problems running pg_dump, make sure you are able to select information from the database using, for example, psql. Also…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics When a direct database connection is specified using the -d option, pg_restore internally executes SQL statements. If you have problems running pg_restore, make sure you are able…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics A failure message mentioning semget or shmget probably indicates you need to configure your kernel to provide adequate shared memory and semaphores. For more discussion see Secti…Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see REINDEX and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any default …Diagnostics DiagnosticsManual ChaptersPG18Diagnostics In case of difficulty, see VACUUM and psql for discussions of potential problems and error messages. The database server must be running at the targeted host. Also, any default c…Diagnostics diagonalFunctionsReferencediagonal Geometric Functions And Operators 13 Extracts box's diagonal as a line segment (same as lseg(box)). diagonal ( box ) → lseg Extracts box's diagonal as a line segment (same as lseg(b…Functions · Geometric Functions And Operators