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debugFunctionsPG18debug ( number ) → same type as input Prints the argument to stderr, and returns the argument. debug(5432.1) → 5432.1pgbench › Notes › Built-In Functions debug_assertionsConfigurationReferencedebug_assertions Preset Options 10 Reports whether PostgreSQL has been built with assertions enabled. That is the case if the macro USE_ASSERT_CHECKING is defined when PostgreSQL is built (a…Configuration · Preset Options debug_copy_parse_plan_treesConfigurationReferencedebug_copy_parse_plan_trees Developer Options 18 Enabling this forces all parse and plan trees to be passed through copyObject(), to facilitate catching errors and omissions in copyObject().…Configuration · Developer Options debug_deadlocksConfigurationReferencedebug_deadlocks Developer Options 10 If set, dumps information about all current locks when a deadlock timeout occurs. This parameter is only available if the LOCK_DEBUG macro was defined wh…Configuration · Developer Options debug_discard_cachesConfigurationReferencedebug_discard_caches Developer Options 14 When set to 1, each system catalog cache entry is invalidated at the first possible opportunity, whether or not anything that would render it invali…Configuration · Developer Options debug_exec_backendConfigurationReferencedebug_exec_backend Preset Options 19 Reports whether PostgreSQL has been built with EXEC_BACKEND enabled. That is the case on Windows or if the macro EXEC_BACKEND is defined when PostgreSQL …Configuration · Preset Options debug_funcsExtensionsExtensionsDebugging and benchmark functions for PostgreSQL buffer and relation locks. debugging locks debug_funcs AdministrationAdministration · Extensions debug_io_directConfigurationReferencedebug_io_direct Developer Options 16 Ask the kernel to minimize caching effects for relation data and WAL files using O_DIRECT (most Unix-like systems), F_NOCACHE (macOS) or FILE_FLAG_NO_BUF…Configuration · Developer Options debug_logical_replication_streamingConfigurationReferencedebug_logical_replication_streaming Developer Options 16 The allowed values are buffered and immediate. The default is buffered. This parameter is intended to be used to test logical decodin…Configuration · Developer Options debug_parallel_queryConfigurationReferencedebug_parallel_query Developer Options 16 Allows the use of parallel queries for testing purposes even in cases where no performance benefit is expected. The allowed values of debug_parallel…Configuration · Developer Options debug_pretty_printConfigurationReferencedebug_pretty_print Reporting and Logging 10 When set, debug_pretty_print indents the messages produced by debug_print_parse, debug_print_rewritten, or debug_print_plan. This results in more …Configuration · Reporting and Logging debug_print_parseConfigurationReferencedebug_print_parse Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or the ex…Configuration · Reporting and Logging debug_print_planConfigurationReferencedebug_print_plan Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or the exe…Configuration · Reporting and Logging debug_print_raw_parseConfigurationReferencedebug_print_raw_parse Reporting and Logging 19 These parameters enable various debugging output to be emitted. When set, they print the resulting raw parse tree, the parse tree, the query re…Configuration · Reporting and Logging debug_print_rewrittenConfigurationReferencedebug_print_rewritten Reporting and Logging 10 These parameters enable various debugging output to be emitted. When set, they print the resulting parse tree, the query rewriter output, or th…Configuration · Reporting and Logging debug_raw_expression_coverage_testConfigurationReferencedebug_raw_expression_coverage_test Developer Options 18 Enabling this forces all raw parse trees for DML statements to be scanned by raw_expression_tree_walker(), to facilitate catching erro…Configuration · Developer Options debug_write_read_parse_plan_treesConfigurationReferencedebug_write_read_parse_plan_trees Developer Options 18 Enabling this forces all parse and plan trees to be passed through outfuncs.c/readfuncs.c, to facilitate catching errors and omissions …Configuration · Developer Options Debugging and Developer SettingsManual ChaptersPG1832.20.2. Debugging and Developer Settings A "dangerous debugging mode" may be enabled by setting the environment variable PGOAUTHDEBUG=UNSAFE. This functionality is provided for ease of loca…Debugging and Developer Settings debversionExtensionsExtensionsDebian version number data type debversion Data typesData types · Extensions decibelExtensionsExtensionsDecibel data type with pressure conversions, arithmetic operators, comparisons, and aggregates data-type decibel measurement pgdecibel Data typesData types · Extensions decimalExtensionsExtensionsDecimal32 and decimal64 decimal floating-point data types with arithmetic and casts numeric type pgDecimal Data typesData types · Extensions Declaration of Array TypesManual ChaptersPG188.15.1. Declaration of Array Types To illustrate the use of array types, we create this table: CREATE TABLE sal_emp ( name text, pay_by_quarter integer[], schedule text[][] ); As shown, an a…Declaration of Array Types Declaration of Composite TypesManual ChaptersPG188.16.1. Declaration of Composite Types Here are two simple examples of defining composite types: CREATE TYPE complex AS ( r double precision, i double precision ); CREATE TYPE inventory_item…Declaration of Composite Types Declaration of Enumerated TypesManual ChaptersPG188.7.1. Declaration of Enumerated Types Enum types are created using the CREATE TYPE command, for example: CREATE TYPE mood AS ENUM ('sad', 'ok', 'happy'); Once created, the enum type can be …Declaration of Enumerated Types DeclarationsManual ChaptersPG1841.3. Declarations All variables used in a block must be declared in the declarations section of the block. (The only exceptions are that the loop variable of a FOR loop iterating over a ran…Declarations Declarative PartitioningManual ChaptersPG185.12.2. Declarative Partitioning PostgreSQL allows you to declare that a table is divided into partitions. The table that is divided is referred to as a partitioned table. The declaration in…Declarative Partitioning DECLAREManual ChaptersPG18DECLARE DECLARE — define a cursor Synopsis DECLARE cursor_name [ BINARY ] [ ASENSITIVE | INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FOR prepared_name DECLARE cursor_n…DECLARE DECLAREManual ChaptersPG18DECLARE DECLARE — define a cursor Synopsis DECLARE name [ BINARY ] [ ASENSITIVE | INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FOR queryDECLARE DECLARESQL CommandsReferenceDECLARE Cursors & Prepared Statements 10 define a cursor DECLARE name [ BINARY ] [ INSENSITIVE ] [ [ NO ] SCROLL ] CURSOR [ { WITH | WITHOUT } HOLD ] FOR query DECLARE allows a user to creat…SQL Commands · Cursors & Prepared Statements Declare SectionsManual ChaptersPG1834.4.2. Declare Sections To pass data from the program to the database, for example as parameters in a query, or to pass data from the database back to the program, the C variables that are …Declare Sections DECLARE STATEMENTManual ChaptersPG18DECLARE STATEMENT DECLARE STATEMENT — declare SQL statement identifier Synopsis EXEC SQL [ AT connection_name ] DECLARE statement_name STATEMENTDECLARE STATEMENT Declaring Cursor VariablesManual ChaptersPG1841.7.1. Declaring Cursor Variables All access to cursors in PL/pgSQL goes through cursor variables, which are always of the special data type refcursor. One way to create a cursor variable i…Declaring Cursor Variables Declaring Function ParametersManual ChaptersPG1841.3.1. Declaring Function Parameters Parameters passed to functions are named with the identifiers $1, $2, etc. Optionally, aliases can be declared for $n parameter names for increased read…Declaring Function Parameters decodeFunctionsReferencedecode Binary String Functions And Operators 10 Decode binary data from textual representation in string. Options for format are same as in encode. decode ( string text, format text ) → byte…Functions · Binary String Functions And Operators decoder_rawExtensionsExtensionsOutput plugin for logical replication in Raw SQL format decoder_raw Replication and streamsReplication and streams · Extensions decoderbufsExtensionsExtensionsLogical decoding plugin that delivers WAL stream changes using a Protocol Buffer format decoderbufs Replication and streamsReplication and streams · Extensions DeduplicationManual ChaptersPG1865.1.4.3. Deduplication A duplicate is a leaf page tuple (a tuple that points to a table row) where all indexed key columns have values that match corresponding column values from at least o…Deduplication Default BehaviorManual ChaptersPG1819.10.3. Default Behavior vacuum_truncate (boolean) # Enables or disables vacuum to try to truncate off any empty pages at the end of the table. The default value is true. If true, VACUUM an…Default Behavior Default Roles Renamed to Predefined RolesManual ChaptersPG18O.2. Default Roles Renamed to Predefined Roles PostgreSQL 13 and below used the term “Default Roles”. However, as these roles are not able to actually be changed and are installed as part of…Default Roles Renamed to Predefined Roles Default ValuesManual ChaptersPG185.2. Default Values A column can be assigned a default value. When a new row is created and no values are specified for some of the columns, those columns will be filled with their respectiv…Default Values