# Sys Schema

- [Sys Schema sys\_config Table](/docs/server/reference/system-tables/sys-schema/sys-schema-sys_config-table.md): The sys\_config table holds persistent configuration options for the Sys Schema, stored using the Aria storage engine to maintain settings across restarts.
- [Sys Schema Stored Functions](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions.md): Explore sys\_schema stored functions in MariaDB Server. These functions simplify querying performance and configuration data, offering a user-friendly interface for database diagnostics.
- [extract\_schema\_from\_file\_name](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/extract_schema_from_file_name.md): This function takes a file path and returns the schema name it belongs to, assuming the file is located within the schema's directory.
- [extract\_table\_from\_file\_name](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/extract_table_from_file_name.md): This function extracts and returns the table name from a given file path, determined solely by parsing the path string.
- [format\_bytes](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/sys_schema_format_bytes.md): Convert bytes to a human-readable string. This function formats a numeric byte count into units like KiB, MiB, GiB, up to EiB.
- [format\_path](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/format_path.md): The format\_path function replaces specific system paths in a given string with their corresponding system variable names for better readability.
- [format\_statement](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/format_statement.md): This function formats and truncates an SQL statement string to a specified length, making it suitable for display in summary views.
- [format\_time](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/format_time.md): The format\_time function converts a time value in picoseconds into a human-readable string with appropriate units (e.g., ms, s, min).
- [list\_add](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/list_add.md): This function appends a value to a comma-separated list of values, which is useful for modifying system variables that take list values.
- [list\_drop](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/list_drop.md): The list\_drop function removes a specified value from a comma-separated list, returning the modified list.
- [ps\_is\_account\_enabled](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_is_account_enabled.md): This function checks whether a specific user account is enabled for instrumentation in the Performance Schema setup\_actors table.
- [ps\_is\_consumer\_enabled](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_is_consumer_enabled.md): This function returns YES or NO indicating whether a specific consumer is currently enabled in the Performance Schema.
- [ps\_is\_instrument\_default\_enabled](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_is_instrument_default_enabled.md): This function checks if a given Performance Schema instrument is enabled by default, returning YES or NO.
- [ps\_is\_instrument\_default\_timed](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_is_instrument_default_timed.md): This function checks if a specific Performance Schema instrument is timed by default, returning YES or NO based on the server's default configuration.
- [ps\_is\_thread\_instrumented](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_is_thread_instrumented.md): The ps\_is\_thread\_instrumented function checks whether a specific thread ID is currently instrumented by the Performance Schema.
- [ps\_thread\_account](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_thread_account.md): This function returns the user account (username@hostname) associated with a specific Performance Schema thread ID.
- [ps\_thread\_id](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_thread_id.md): The ps\_thread\_id function returns the internal Performance Schema thread ID associated with a given connection ID.
- [ps\_thread\_stack](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_thread_stack.md): This function returns a JSON-formatted stack trace of all statements, stages, and events for a given thread, useful for deep diagnostics.
- [ps\_thread\_trx\_info](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/ps_thread_trx_info.md): The ps\_thread\_trx\_info function returns a JSON object detailing the current transaction and executed statements for a specific thread.
- [quote\_identifier](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/quote_identifier.md): This function quotes a given string with backticks to ensure it can be safely used as an identifier in SQL statements.
- [sys\_get\_config](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/sys_get_config.md): The sys\_get\_config function retrieves the value of a specified configuration option from the sys\_config table, or a user variable if set.
- [version\_major](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/version_major.md): This function returns the major version number of the MariaDB Server instance (e.g., 10 from 10.6.4).
- [version\_minor](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/version_minor.md): This function returns the minor version number of the MariaDB Server instance, such as the 6 in 10.6.4.
- [version\_patch](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-functions/version_patch.md): This function returns the patch release version number of the MariaDB Server instance, such as the 4 in 10.6.4.
- [Sys Schema Stored Procedures](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures.md): Explore sys\_schema stored procedures in MariaDB Server. These procedures simplify complex administrative and diagnostic tasks, offering streamlined access to performance and configuration insights.
- [create\_synonym\_db](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/create_synonym_db.md): The create\_synonym\_db stored procedure creates a new database that contains views mirroring all tables from a source database, useful for creating aliases.
- [optimizer\_switch Helper Functions](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/optimizer_switch-helper-functions.md): These helper functions allow you to easily enable or disable specific optimizer\_switch flags for the current session.
- [ps\_trace\_statement\_digest](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/ps_trace_statement_digest.md): This procedure traces a specific statement digest in the Performance Schema, capturing details about its execution for performance analysis.
- [ps\_trace\_thread](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/ps_trace_thread.md): The ps\_trace\_thread procedure captures a trace of Performance Schema instrumentation for a specific thread and dumps it to a .dot formatted graph file.
- [ps\_truncate\_all\_tables](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/ps_truncate_all_tables.md): This procedure truncates all Performance Schema summary tables, effectively resetting all aggregated performance statistics.
- [statement\_performance\_analyzer](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/statement_performance_analyzer.md): This diagnostic procedure creates a report of the statements currently running or recently run on the server, aiding in performance troubleshooting.
- [table\_exists](/docs/server/reference/system-tables/sys-schema/sys-schema-stored-procedures/table_exists.md): The table\_exists procedure checks for the existence of a specific table, view, or temporary table within a given database.
- [Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views.md): Explore sys\_schema views in MariaDB Server. These views offer simplified, aggregated insights into server performance, I/O, and memory usage, making diagnostics and monitoring easier.
- [host\_summary and x$host\_summary Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/host_summary-and-xhost_summary-sys-schema-views.md): The host\_summary views provide a high-level overview of activity per client host, including statement counts, file I/O, and connection statistics.
- [host\_summary\_by\_file\_io and x$host\_summary\_by\_file\_io Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/host_summary_by_file_io-and-xhost_summary_by_file_io-sys-schema-views.md): These views summarize file I/O events grouped by client host, detailing total I/O counts and latency to identify hosts generating heavy disk traffic.
- [host\_summary\_by\_file\_io\_type and x$host\_summary\_by\_file\_io\_type Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/host_summary_by_file_io_type-and-xhost_summary_by_file_io_type-sys-schema-v.md): These views provide a breakdown of file I/O events by event type (e.g., read, write) for each host, helping to characterize the I/O workload.
- [host\_summary\_by\_stages and x$host\_summary\_by\_stages Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/host_summary_by_stages-and-xhost_summary_by_stages-sys-schema-views.md): These views summarize statement execution stages grouped by host, showing where threads spend the most time during query processing.
- [host\_summary\_by\_statement\_type and x$host\_summary\_by\_statement\_type Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/host_summary_by_statement_type-and-xhost_summary_by_statement_type-sys-sche.md): These views aggregate executed statements by type (e.g., SELECT, INSERT) and host, providing statistics on frequency and latency.
- [host\_summary\_by\_statement\_latency and x$host\_summary\_by\_statement\_latency Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/sys-schema-views-host_summary_by_statement_latency-and-xhost_summary_by_sta.md): These views summarize statement statistics grouped by host, sorted by total latency, helping to identify hosts running the most time-consuming queries.
- [innodb\_buffer\_stats\_by\_schema and x$innodb\_buffer\_stats\_by\_schema Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/innodb_buffer_stats_by_schema-and-xinnodb_buffer_stats_by_schema-sys-schema.md): These views summarize InnoDB buffer pool usage, showing the amount of memory and number of pages allocated to each database schema.
- [innodb\_buffer\_stats\_by\_table and x$innodb\_buffer\_stats\_by\_table Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/innodb_buffer_stats_by_table-and-xinnodb_buffer_stats_by_table-sys-schema-v.md): These views provide a granular breakdown of InnoDB buffer pool usage by individual tables, sorted by buffer allocation size.
- [innodb\_lock\_waits and x$innodb\_lock\_waits Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/innodb_lock_waits-and-xinnodb_lock_waits-sys-schema-views.md): These views summarize lock wait information, linking waiting transactions to blocking transactions to help diagnose deadlocks and contention.
- [io\_by\_thread\_by\_latency and x$io\_by\_thread\_by\_latency Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/io_by_thread_by_latency-and-xio_by_thread_by_latency-sys-schema-views.md): These views rank threads by I/O latency, making it easier to identify specific threads that are consuming the most disk resources.
- [io\_global\_by\_file\_by\_bytes and x$io\_global\_by\_file\_by\_bytes Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/io_global_by_file_by_bytes-and-xio_global_by_file_by_bytes-sys-schema-views.md): These views summarize global file I/O statistics grouped by file path, sorted by total bytes read and written.
- [io\_global\_by\_file\_by\_latency and x$io\_global\_by\_file\_by\_latency Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/io_global_by_file_by_latency-and-xio_global_by_file_by_latency-sys-schema-v.md): These views summarize global file I/O statistics grouped by file path, sorted by total latency to highlight slow I/O targets.
- [io\_global\_by\_wait\_by\_bytes and x$io\_global\_by\_wait\_by\_bytes Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/io_global_by_wait_by_bytes-and-xio_global_by_wait_by_bytes-sys-schema-views.md): These views summarize global I/O consumers by event name, displaying total bytes read and written to identify high-throughput events.
- [io\_global\_by\_wait\_by\_latency and x$io\_global\_by\_wait\_by\_latency Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/io_global_by_wait_by_latency-and-xio_global_by_wait_by_latency-sys-schema-v.md): These views summarize global I/O consumers by event name, sorted by total latency, helping to pinpoint slow I/O event types.
- [latest\_file\_io and x$latest\_file\_io Sys Schema Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/latest_file_io-and-xlatest_file_io-sys-schema-views.md): These views display the most recent file I/O events, providing a real-time look at which files are being accessed by the server.
- [memory\_by\_host\_by\_current\_bytes and x$memory\_by\_host\_by\_current\_bytes Views](/docs/server/reference/system-tables/sys-schema/sys-schema-views/memory_by_host_by_current_bytes-and-xmemory_by_host_by_current_bytes-views.md): These views summarize current memory usage grouped by client host, enabling administrators to track memory consumption per connected host.
- [metrics Sys Schema View](/docs/server/reference/system-tables/sys-schema/sys-schema-views/metrics-sys-schema-view.md): The metrics view consolidates key performance metrics from Global Status, InnoDB Metrics, and memory summaries into a single unified table.
- [privileges\_by\_table\_by\_level Sys Schema View](/docs/server/reference/system-tables/sys-schema/sys-schema-views/privileges_by_table_by_level-sys-schema-view.md): The privileges\_by\_table\_by\_level view lists granted privileges broken down by table and the level (Global, Schema, or Table) at which they were granted.
- [schema\_auto\_increment\_columns Sys Schema View](/docs/server/reference/system-tables/sys-schema/sys-schema-views/schema_auto_increment_columns-sys-schema-view.md): The schema\_auto\_increment\_columns view lists tables with AUTO\_INCREMENT columns, showing the current value and the maximum allowed value for the column type.
- [schema\_object\_overview Sys Schema View](/docs/server/reference/system-tables/sys-schema/sys-schema-views/schema_object_overview-sys-schema-view.md): The schema\_object\_overview view provides a count of different database objects (such as tables, views, and routines) within each schema on the server.