PostgreSQL GUC 参数级别介绍-阿里云开发者社区

开发者社区> 阿里云数据库> 正文
登录阅读全文

PostgreSQL GUC 参数级别介绍

简介:

标签

PostgreSQL , 参数 , 参数级别


背景

在添加GUC参数时,需要注意你添加的参数属于什么类别的参数。

例如如果你想让普通用户能随时修改它,那么你需要将参数级别设置为PGC_USERSET。如果你想让超级用户能在线修改它,那么你需要将它设置为PGC_SUSET。如果你想让它能够在修改配置参数并通过信号生效,那么需要设置为PGC_SIGHUP。

GUC参数相关的代码如下

src/backend/utils/misc/guc.c

参数级别介绍

/*  
 * Displayable names for context types (enum GucContext)  
 *  
 * Note: these strings are deliberately not localized.  
 */  
const char *const GucContext_Names[] =  
{  
         /* PGC_INTERNAL */ "internal",      编译数据库集群时设置  
         /* PGC_POSTMASTER */ "postmaster",  只能启动是设置  
         /* PGC_SIGHUP */ "sighup",          允许通过修改配置文件,并通过SIGHUP信号更新参数。  
         /* PGC_SU_BACKEND */ "superuser-backend",     超级用户的backend级参数  
         /* PGC_BACKEND */ "backend",                  普通用户的backend级参数  
         /* PGC_SUSET */ "superuser",                  允许超级用户在线修改的参数  
         /* PGC_USERSET */ "user"                      允许普通用户在线修改的参数  
};  

如何查看所有参数级别

postgres=# select context,name,short_desc from pg_settings order by context,category,name;  
      context      |                name                 |                                                          short_desc                                                             
-------------------+-------------------------------------+-------------------------------------------------------------------------------------------------------------------------------  
 backend           | ignore_system_indexes               | Disables reading from system indexes.  
 backend           | post_auth_delay                     | Waits N seconds on connection startup after authentication.  
 internal          | lc_collate                          | Shows the collation order locale.  
 internal          | lc_ctype                            | Shows the character classification and case conversion locale.  
 internal          | server_encoding                     | Sets the server (database) character set encoding.  
 internal          | block_size                          | Shows the size of a disk block.  
 internal          | data_checksums                      | Shows whether data checksums are turned on for this cluster.  
 internal          | debug_assertions                    | Shows whether the running server has assertion checks enabled.  
 internal          | integer_datetimes                   | Datetimes are integer based.  
 internal          | max_function_args                   | Shows the maximum number of function arguments.  
 internal          | max_identifier_length               | Shows the maximum identifier length.  
 internal          | max_index_keys                      | Shows the maximum number of index keys.  
 internal          | segment_size                        | Shows the number of pages per disk file.  
 internal          | server_version                      | Shows the server version.  
 internal          | server_version_num                  | Shows the server version as an integer.  
 internal          | wal_block_size                      | Shows the block size in the write ahead log.  
 internal          | wal_segment_size                    | Shows the number of pages per write ahead log segment.  
 postmaster        | autovacuum_freeze_max_age           | Age at which to autovacuum a table to prevent transaction ID wraparound.  
 postmaster        | autovacuum_max_workers              | Sets the maximum number of simultaneously running autovacuum worker processes.  
 postmaster        | autovacuum_multixact_freeze_max_age | Multixact age at which to autovacuum a table to prevent multixact wraparound.  
 postmaster        | shared_preload_libraries            | Lists shared libraries to preload into server.  
 postmaster        | bonjour                             | Enables advertising the server via Bonjour.  
 postmaster        | bonjour_name                        | Sets the Bonjour service name.  
 postmaster        | listen_addresses                    | Sets the host name or IP address(es) to listen to.  
 postmaster        | max_connections                     | Sets the maximum number of concurrent connections.  
 postmaster        | port                                | Sets the TCP port the server listens on.  
 postmaster        | superuser_reserved_connections      | Sets the number of connection slots reserved for superusers.  
 postmaster        | unix_socket_directories             | Sets the directories where Unix-domain sockets will be created.  
 postmaster        | unix_socket_group                   | Sets the owning group of the Unix-domain socket.  
 postmaster        | unix_socket_permissions             | Sets the access permissions of the Unix-domain socket.  
 postmaster        | allow_system_table_mods             | Allows modifications of the structure of system tables.  
 postmaster        | config_file                         | Sets the server's main configuration file.  
 postmaster        | data_directory                      | Sets the server's data directory.  
 postmaster        | external_pid_file                   | Writes the postmaster PID to the specified file.  
 postmaster        | hba_file                            | Sets the server's "hba" configuration file.  
 postmaster        | ident_file                          | Sets the server's "ident" configuration file.  
 postmaster        | max_locks_per_transaction           | Sets the maximum number of locks per transaction.  
 postmaster        | max_pred_locks_per_transaction      | Sets the maximum number of predicate locks per transaction.  
 postmaster        | cluster_name                        | Sets the name of the cluster, which is included in the process title.  
 postmaster        | track_commit_timestamp              | Collects transaction commit time.  
 postmaster        | max_replication_slots               | Sets the maximum number of simultaneously defined replication slots.  
 postmaster        | max_wal_senders                     | Sets the maximum number of simultaneously running WAL sender processes.  
 postmaster        | hot_standby                         | Allows connections and queries during recovery.  
 postmaster        | max_logical_replication_workers     | Maximum number of logical replication worker processes.  
 postmaster        | event_source                        | Sets the application name used to identify PostgreSQL messages in the event log.  
 postmaster        | logging_collector                   | Start a subprocess to capture stderr output and/or csvlogs into log files.  
 postmaster        | max_worker_processes                | Maximum number of concurrent worker processes.  
 postmaster        | old_snapshot_threshold              | Time before a snapshot is too old to read pages changed after the snapshot was taken.  
 postmaster        | max_files_per_process               | Sets the maximum number of simultaneously open files for each server process.  
 postmaster        | dynamic_shared_memory_type          | Selects the dynamic shared memory implementation used.  
 postmaster        | huge_pages                          | Use of huge pages on Linux.  
 postmaster        | max_prepared_transactions           | Sets the maximum number of simultaneously prepared transactions.  
 postmaster        | shared_buffers                      | Sets the number of shared memory buffers used by the server.  
 postmaster        | track_activity_query_size           | Sets the size reserved for pg_stat_activity.query, in bytes.  
 postmaster        | archive_mode                        | Allows archiving of WAL files using archive_command.  
 postmaster        | wal_buffers                         | Sets the number of disk-page buffers in shared memory for WAL.  
 postmaster        | wal_level                           | Set the level of information written to the WAL.  
 postmaster        | wal_log_hints                       | Writes full pages to WAL when first modified after a checkpoint, even for a non-critical modifications.  
 sighup            | autovacuum                          | Starts the autovacuum subprocess.  
 sighup            | autovacuum_analyze_scale_factor     | Number of tuple inserts, updates, or deletes prior to analyze as a fraction of reltuples.  
 sighup            | autovacuum_analyze_threshold        | Minimum number of tuple inserts, updates, or deletes prior to analyze.  
 sighup            | autovacuum_naptime                  | Time to sleep between autovacuum runs.  
 sighup            | autovacuum_vacuum_cost_delay        | Vacuum cost delay in milliseconds, for autovacuum.  
 sighup            | autovacuum_vacuum_cost_limit        | Vacuum cost amount available before napping, for autovacuum.  
 sighup            | autovacuum_vacuum_scale_factor      | Number of tuple updates or deletes prior to vacuum as a fraction of reltuples.  
 sighup            | autovacuum_vacuum_threshold         | Minimum number of tuple updates or deletes prior to vacuum.  
 sighup            | authentication_timeout              | Sets the maximum allowed time to complete client authentication.  
 sighup            | db_user_namespace                   | Enables per-database user names.  
 sighup            | krb_caseins_users                   | Sets whether Kerberos and GSSAPI user names should be treated as case-insensitive.  
 sighup            | krb_server_keyfile                  | Sets the location of the Kerberos server key file.  
 sighup            | ssl                                 | Enables SSL connections.  
 sighup            | ssl_ca_file                         | Location of the SSL certificate authority file.  
 sighup            | ssl_cert_file                       | Location of the SSL server certificate file.  
 sighup            | ssl_ciphers                         | Sets the list of allowed SSL ciphers.  
 sighup            | ssl_crl_file                        | Location of the SSL certificate revocation list file.  
 sighup            | ssl_dh_params_file                  | Location of the SSL DH params file.  
 sighup            | ssl_ecdh_curve                      | Sets the curve to use for ECDH.  
 sighup            | ssl_key_file                        | Location of the SSL server private key file.  
 sighup            | ssl_prefer_server_ciphers           | Give priority to server ciphersuite order.  
 sighup            | pre_auth_delay                      | Waits N seconds on connection startup before authentication.  
 sighup            | trace_recovery_messages             | Enables logging of recovery-related debugging information.  
 sighup            | restart_after_crash                 | Reinitialize server after backend crash.  
 sighup            | max_pred_locks_per_page             | Sets the maximum number of predicate-locked tuples per page.  
 sighup            | max_pred_locks_per_relation         | Sets the maximum number of predicate-locked pages and tuples per relation.  
 sighup            | synchronous_standby_names           | Number of synchronous standbys and list of names of potential synchronous ones.  
 sighup            | vacuum_defer_cleanup_age            | Number of transactions by which VACUUM and HOT cleanup should be deferred, if any.  
 sighup            | wal_keep_segments                   | Sets the number of WAL files held for standby servers.  
 sighup            | wal_sender_timeout                  | Sets the maximum time to wait for WAL replication.  
 sighup            | hot_standby_feedback                | Allows feedback from a hot standby to the primary that will avoid query conflicts.  
 sighup            | max_standby_archive_delay           | Sets the maximum delay before canceling queries when a hot standby server is processing archived WAL data.  
 sighup            | max_standby_streaming_delay         | Sets the maximum delay before canceling queries when a hot standby server is processing streamed WAL data.  
 sighup            | wal_receiver_status_interval        | Sets the maximum interval between WAL receiver status reports to the primary.  
 sighup            | wal_receiver_timeout                | Sets the maximum wait time to receive data from the primary.  
 sighup            | wal_retrieve_retry_interval         | Sets the time to wait before retrying to retrieve WAL after a failed attempt.  
 sighup            | max_sync_workers_per_subscription   | Maximum number of table synchronization workers per subscription.  
 sighup            | log_autovacuum_min_duration         | Sets the minimum execution time above which autovacuum actions will be logged.  
 sighup            | log_checkpoints                     | Logs each checkpoint.  
 sighup            | log_hostname                        | Logs the host name in the connection logs.  
 sighup            | log_line_prefix                     | Controls information prefixed to each log line.  
 sighup            | log_timezone                        | Sets the time zone to use in log messages.  
 sighup            | log_destination                     | Sets the destination for server log output.  
 sighup            | log_directory                       | Sets the destination directory for log files.  
 sighup            | log_file_mode                       | Sets the file permissions for log files.  
 sighup            | log_filename                        | Sets the file name pattern for log files.  
 sighup            | log_rotation_age                    | Automatic log file rotation will occur after N minutes.  
 sighup            | log_rotation_size                   | Automatic log file rotation will occur after N kilobytes.  
 sighup            | log_truncate_on_rotation            | Truncate existing log files of same name during log rotation.  
 sighup            | syslog_facility                     | Sets the syslog "facility" to be used when syslog enabled.  
 sighup            | syslog_ident                        | Sets the program name used to identify PostgreSQL messages in syslog.  
 sighup            | syslog_sequence_numbers             | Add sequence number to syslog messages to avoid duplicate suppression.  
 sighup            | syslog_split_messages               | Split messages sent to syslog by lines and to fit into 1024 bytes.  
 sighup            | bgwriter_delay                      | Background writer sleep time between rounds.  
 sighup            | bgwriter_flush_after                | Number of pages after which previously performed writes are flushed to disk.  
 sighup            | bgwriter_lru_maxpages               | Background writer maximum number of LRU pages to flush per round.  
 sighup            | bgwriter_lru_multiplier             | Multiple of the average buffer usage to free per round.  
 sighup            | autovacuum_work_mem                 | Sets the maximum memory to be used by each autovacuum worker process.  
 sighup            | stats_temp_directory                | Writes temporary statistics files to the specified directory.  
 sighup            | archive_command                     | Sets the shell command that will be called to archive a WAL file.  
 sighup            | archive_timeout                     | Forces a switch to the next WAL file if a new file has not been started within N seconds.  
 sighup            | checkpoint_completion_target        | Time spent flushing dirty buffers during checkpoint, as fraction of checkpoint interval.  
 sighup            | checkpoint_flush_after              | Number of pages after which previously performed writes are flushed to disk.  
 sighup            | checkpoint_timeout                  | Sets the maximum time between automatic WAL checkpoints.  
 sighup            | checkpoint_warning                  | Enables warnings if checkpoint segments are filled more frequently than this.  
 sighup            | max_wal_size                        | Sets the WAL size that triggers a checkpoint.  
 sighup            | min_wal_size                        | Sets the minimum size to shrink the WAL to.  
 sighup            | fsync                               | Forces synchronization of updates to disk.  
 sighup            | full_page_writes                    | Writes full pages to WAL when first modified after a checkpoint.  
 sighup            | wal_sync_method                     | Selects the method used for forcing WAL updates to disk.  
 sighup            | wal_writer_delay                    | Time between WAL flushes performed in the WAL writer.  
 sighup            | wal_writer_flush_after              | Amount of WAL written out by WAL writer that triggers a flush.  
 superuser         | lc_messages                         | Sets the language in which messages are displayed.  
 superuser         | dynamic_library_path                | Sets the path for dynamically loadable modules.  
 superuser         | session_preload_libraries           | Lists shared libraries to preload into each backend.  
 superuser         | session_replication_role            | Sets the session's behavior for triggers and rewrite rules.  
 superuser         | ignore_checksum_failure             | Continues processing after a checksum failure.  
 superuser         | wal_consistency_checking            | Sets the WAL resource managers for which WAL consistency checks are done.  
 superuser         | zero_damaged_pages                  | Continues processing past damaged page headers.  
 superuser         | deadlock_timeout                    | Sets the time to wait on a lock before checking for deadlock.  
 superuser         | update_process_title                | Updates the process title to show the active SQL command.  
 superuser         | log_duration                        | Logs the duration of each completed SQL statement.  
 superuser         | log_error_verbosity                 | Sets the verbosity of logged messages.  
 superuser         | log_lock_waits                      | Logs long lock waits.  
 superuser         | log_replication_commands            | Logs each replication command.  
 superuser         | log_statement                       | Sets the type of statements logged.  
 superuser         | log_temp_files                      | Log the use of temporary files larger than this number of kilobytes.  
 superuser         | log_min_duration_statement          | Sets the minimum execution time above which statements will be logged.  
 superuser         | log_min_error_statement             | Causes all statements generating error at or above this level to be logged.  
 superuser         | log_min_messages                    | Sets the message levels that are logged.  
 superuser         | temp_file_limit                     | Limits the total size of all temporary files used by each process.  
 superuser         | max_stack_depth                     | Sets the maximum stack depth, in kilobytes.  
 superuser         | log_executor_stats                  | Writes executor performance statistics to the server log.  
 superuser         | log_parser_stats                    | Writes parser performance statistics to the server log.  
 superuser         | log_planner_stats                   | Writes planner performance statistics to the server log.  
 superuser         | log_statement_stats                 | Writes cumulative performance statistics to the server log.  
 superuser         | track_activities                    | Collects information about executing commands.  
 superuser         | track_counts                        | Collects statistics on database activity.  
 superuser         | track_functions                     | Collects function-level statistics on database activity.  
 superuser         | track_io_timing                     | Collects timing statistics for database I/O activity.  
 superuser         | lo_compat_privileges                | Enables backward compatibility mode for privilege checks on large objects.  
 superuser         | commit_delay                        | Sets the delay in microseconds between transaction commit and flushing WAL to disk.  
 superuser         | wal_compression                     | Compresses full-page writes written in WAL file.  
 superuser-backend | log_connections                     | Logs each successful connection.  
 superuser-backend | log_disconnections                  | Logs end of a session, including duration.  
 user              | DateStyle                           | Sets the display format for date and time values.  
 user              | IntervalStyle                       | Sets the display format for interval values.  
 user              | TimeZone                            | Sets the time zone for displaying and interpreting time stamps.  
 user              | client_encoding                     | Sets the client's character set encoding.  
 user              | default_text_search_config          | Sets default text search configuration.  
 user              | extra_float_digits                  | Sets the number of digits displayed for floating-point values.  
 user              | lc_monetary                         | Sets the locale for formatting monetary amounts.  
 user              | lc_numeric                          | Sets the locale for formatting numbers.  
 user              | lc_time                             | Sets the locale for formatting date and time values.  
 user              | timezone_abbreviations              | Selects a file of time zone abbreviations.  
 user              | gin_fuzzy_search_limit              | Sets the maximum allowed result for exact search by GIN.  
 user              | tcp_keepalives_count                | Maximum number of TCP keepalive retransmits.  
 user              | tcp_keepalives_idle                 | Time between issuing TCP keepalives.  
 user              | tcp_keepalives_interval             | Time between TCP keepalive retransmits.  
 user              | local_preload_libraries             | Lists unprivileged shared libraries to preload into each backend.  
 user              | bytea_output                        | Sets the output format for bytea.  
 user              | check_function_bodies               | Check function bodies during CREATE FUNCTION.  
 user              | default_tablespace                  | Sets the default tablespace to create tables and indexes in.  
 user              | default_transaction_deferrable      | Sets the default deferrable status of new transactions.  
 user              | default_transaction_isolation       | Sets the transaction isolation level of each new transaction.  
 user              | default_transaction_read_only       | Sets the default read-only status of new transactions.  
 user              | gin_pending_list_limit              | Sets the maximum size of the pending list for GIN index.  
 user              | idle_in_transaction_session_timeout | Sets the maximum allowed duration of any idling transaction.  
 user              | lock_timeout                        | Sets the maximum allowed duration of any wait for a lock.  
 user              | search_path                         | Sets the schema search order for names that are not schema-qualified.  
 user              | statement_timeout                   | Sets the maximum allowed duration of any statement.  
 user              | temp_tablespaces                    | Sets the tablespace(s) to use for temporary tables and sort files.  
 user              | transaction_deferrable              | Whether to defer a read-only serializable transaction until it can be executed with no possible serialization failures.  
 user              | transaction_isolation               | Sets the current transaction's isolation level.  
 user              | transaction_read_only               | Sets the current transaction's read-only status.  
 user              | vacuum_freeze_min_age               | Minimum age at which VACUUM should freeze a table row.  
 user              | vacuum_freeze_table_age             | Age at which VACUUM should scan whole table to freeze tuples.  
 user              | vacuum_multixact_freeze_min_age     | Minimum age at which VACUUM should freeze a MultiXactId in a table row.  
 user              | vacuum_multixact_freeze_table_age   | Multixact age at which VACUUM should scan whole table to freeze tuples.  
 user              | xmlbinary                           | Sets how binary values are to be encoded in XML.  
 user              | xmloption                           | Sets whether XML data in implicit parsing and serialization operations is to be considered as documents or content fragments.  
 user              | password_encryption                 | Encrypt passwords.  
 user              | row_security                        | Enable row security.  
 user              | trace_notify                        | Generates debugging output for LISTEN and NOTIFY.  
 user              | trace_sort                          | Emit information about resource usage in sorting.  
 user              | exit_on_error                       | Terminate session on any error.  
 user              | geqo                                | Enables genetic query optimization.  
 user              | geqo_effort                         | GEQO: effort is used to set the default for other GEQO parameters.  
 user              | geqo_generations                    | GEQO: number of iterations of the algorithm.  
 user              | geqo_pool_size                      | GEQO: number of individuals in the population.  
 user              | geqo_seed                           | GEQO: seed for random path selection.  
 user              | geqo_selection_bias                 | GEQO: selective pressure within the population.  
 user              | geqo_threshold                      | Sets the threshold of FROM items beyond which GEQO is used.  
 user              | constraint_exclusion                | Enables the planner to use constraints to optimize queries.  
 user              | cursor_tuple_fraction               | Sets the planner's estimate of the fraction of a cursor's rows that will be retrieved.  
 user              | default_statistics_target           | Sets the default statistics target.  
 user              | force_parallel_mode                 | Forces use of parallel query facilities.  
 user              | from_collapse_limit                 | Sets the FROM-list size beyond which subqueries are not collapsed.  
 user              | join_collapse_limit                 | Sets the FROM-list size beyond which JOIN constructs are not flattened.  
 user              | cpu_index_tuple_cost                | Sets the planner's estimate of the cost of processing each index entry during an index scan.  
 user              | cpu_operator_cost                   | Sets the planner's estimate of the cost of processing each operator or function call.  
 user              | cpu_tuple_cost                      | Sets the planner's estimate of the cost of processing each tuple (row).  
 user              | effective_cache_size                | Sets the planner's assumption about the size of the disk cache.  
 user              | min_parallel_index_scan_size        | Sets the minimum amount of index data for a parallel scan.  
 user              | min_parallel_table_scan_size        | Sets the minimum amount of table data for a parallel scan.  
 user              | parallel_setup_cost                 | Sets the planner's estimate of the cost of starting up worker processes for parallel query.  
 user              | parallel_tuple_cost                 | Sets the planner's estimate of the cost of passing each tuple (row) from worker to master backend.  
 user              | random_page_cost                    | Sets the planner's estimate of the cost of a nonsequentially fetched disk page.  
 user              | seq_page_cost                       | Sets the planner's estimate of the cost of a sequentially fetched disk page.  
 user              | enable_bitmapscan                   | Enables the planner's use of bitmap-scan plans.  
 user              | enable_gathermerge                  | Enables the planner's use of gather merge plans.  
 user              | enable_hashagg                      | Enables the planner's use of hashed aggregation plans.  
 user              | enable_hashjoin                     | Enables the planner's use of hash join plans.  
 user              | enable_indexonlyscan                | Enables the planner's use of index-only-scan plans.  
 user              | enable_indexscan                    | Enables the planner's use of index-scan plans.  
 user              | enable_material                     | Enables the planner's use of materialization.  
 user              | enable_mergejoin                    | Enables the planner's use of merge join plans.  
 user              | enable_nestloop                     | Enables the planner's use of nested-loop join plans.  
 user              | enable_parallelappend               | Enables the planner's use of parallel append plans.  
 user              | enable_seqscan                      | Enables the planner's use of sequential-scan plans.  
 user              | enable_sort                         | Enables the planner's use of explicit sort steps.  
 user              | enable_tidscan                      | Enables the planner's use of TID scan plans.  
 user              | application_name                    | Sets the application name to be reported in statistics and logs.  
 user              | debug_pretty_print                  | Indents parse and plan tree displays.  
 user              | debug_print_parse                   | Logs each query's parse tree.  
 user              | debug_print_plan                    | Logs each query's execution plan.  
 user              | debug_print_rewritten               | Logs each query's rewritten parse tree.  
 user              | client_min_messages                 | Sets the message levels that are sent to the client.  
 user              | backend_flush_after                 | Number of pages after which previously performed writes are flushed to disk.  
 user              | effective_io_concurrency            | Number of simultaneous requests that can be handled efficiently by the disk subsystem.  
 user              | max_parallel_workers                | Sets the maximum number of parallel workers than can be active at one time.  
 user              | max_parallel_workers_per_gather     | Sets the maximum number of parallel processes per executor node.  
 user              | vacuum_cost_delay                   | Vacuum cost delay in milliseconds.  
 user              | vacuum_cost_limit                   | Vacuum cost amount available before napping.  
 user              | vacuum_cost_page_dirty              | Vacuum cost for a page dirtied by vacuum.  
 user              | vacuum_cost_page_hit                | Vacuum cost for a page found in the buffer cache.  
 user              | vacuum_cost_page_miss               | Vacuum cost for a page not found in the buffer cache.  
 user              | maintenance_work_mem                | Sets the maximum memory to be used for maintenance operations.  
 user              | replacement_sort_tuples             | Sets the maximum number of tuples to be sorted using replacement selection.  
 user              | temp_buffers                        | Sets the maximum number of temporary buffers used by each session.  
 user              | work_mem                            | Sets the maximum memory to be used for query workspaces.  
 user              | transform_null_equals               | Treats "expr=NULL" as "expr IS NULL".  
 user              | array_nulls                         | Enable input of NULL elements in arrays.  
 user              | backslash_quote                     | Sets whether "\'" is allowed in string literals.  
 user              | default_with_oids                   | Create new tables with OIDs by default.  
 user              | escape_string_warning               | Warn about backslash escapes in ordinary string literals.  
 user              | operator_precedence_warning         | Emit a warning for constructs that changed meaning since PostgreSQL 9.4.  
 user              | quote_all_identifiers               | When generating SQL fragments, quote all identifiers.  
 user              | standard_conforming_strings         | Causes '...' strings to treat backslashes literally.  
 user              | synchronize_seqscans                | Enable synchronized sequential scans.  
 user              | commit_siblings                     | Sets the minimum concurrent open transactions before performing commit_delay.  
 user              | synchronous_commit                  | Sets the current transaction's synchronization level.  
(270 rows)  

版权声明:本文内容由阿里云实名注册用户自发贡献,版权归原作者所有,阿里云开发者社区不拥有其著作权,亦不承担相应法律责任。具体规则请查看《阿里云开发者社区用户服务协议》和《阿里云开发者社区知识产权保护指引》。如果您发现本社区中有涉嫌抄袭的内容,填写侵权投诉表单进行举报,一经查实,本社区将立刻删除涉嫌侵权内容。

分享: