2021-12-01 11:12:48 -07:00
<!DOCTYPE HTML>
< html lang = "en" class = "sidebar-visible no-js light" >
< head >
<!-- Book generated using mdBook -->
< meta charset = "UTF-8" >
< title > Useful SQL for Admins - Synapse< / title >
<!-- Custom HTML head -->
< meta content = "text/html; charset=utf-8" http-equiv = "Content-Type" >
< meta name = "description" content = "" >
< meta name = "viewport" content = "width=device-width, initial-scale=1" >
< meta name = "theme-color" content = "#ffffff" / >
< link rel = "icon" href = "../../favicon.svg" >
< link rel = "shortcut icon" href = "../../favicon.png" >
< link rel = "stylesheet" href = "../../css/variables.css" >
< link rel = "stylesheet" href = "../../css/general.css" >
< link rel = "stylesheet" href = "../../css/chrome.css" >
< link rel = "stylesheet" href = "../../css/print.css" media = "print" >
<!-- Fonts -->
< link rel = "stylesheet" href = "../../FontAwesome/css/font-awesome.css" >
< link rel = "stylesheet" href = "../../fonts/fonts.css" >
<!-- Highlight.js Stylesheets -->
< link rel = "stylesheet" href = "../../highlight.css" >
< link rel = "stylesheet" href = "../../tomorrow-night.css" >
< link rel = "stylesheet" href = "../../ayu-highlight.css" >
<!-- Custom theme stylesheets -->
< link rel = "stylesheet" href = "../../docs/website_files/table-of-contents.css" >
< link rel = "stylesheet" href = "../../docs/website_files/remove-nav-buttons.css" >
< link rel = "stylesheet" href = "../../docs/website_files/indent-section-headers.css" >
< / head >
< body >
<!-- Provide site root to javascript -->
< script type = "text/javascript" >
var path_to_root = "../../";
var default_theme = window.matchMedia("(prefers-color-scheme: dark)").matches ? "navy" : "light";
< / script >
<!-- Work around some values being stored in localStorage wrapped in quotes -->
< script type = "text/javascript" >
try {
var theme = localStorage.getItem('mdbook-theme');
var sidebar = localStorage.getItem('mdbook-sidebar');
if (theme.startsWith('"') & & theme.endsWith('"')) {
localStorage.setItem('mdbook-theme', theme.slice(1, theme.length - 1));
}
if (sidebar.startsWith('"') & & sidebar.endsWith('"')) {
localStorage.setItem('mdbook-sidebar', sidebar.slice(1, sidebar.length - 1));
}
} catch (e) { }
< / script >
<!-- Set the theme before any content is loaded, prevents flash -->
< script type = "text/javascript" >
var theme;
try { theme = localStorage.getItem('mdbook-theme'); } catch(e) { }
if (theme === null || theme === undefined) { theme = default_theme; }
var html = document.querySelector('html');
html.classList.remove('no-js')
html.classList.remove('light')
html.classList.add(theme);
html.classList.add('js');
< / script >
<!-- Hide / unhide sidebar before it is displayed -->
< script type = "text/javascript" >
var html = document.querySelector('html');
var sidebar = 'hidden';
if (document.body.clientWidth >= 1080) {
try { sidebar = localStorage.getItem('mdbook-sidebar'); } catch(e) { }
sidebar = sidebar || 'visible';
}
html.classList.remove('sidebar-visible');
html.classList.add("sidebar-" + sidebar);
< / script >
< nav id = "sidebar" class = "sidebar" aria-label = "Table of contents" >
< div class = "sidebar-scrollbox" >
2023-01-31 11:37:46 -07:00
< ol class = "chapter" > < li class = "chapter-item expanded affix " > < li class = "part-title" > Introduction< / li > < li class = "chapter-item expanded " > < a href = "../../welcome_and_overview.html" > Welcome and Overview< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Setup< / li > < li class = "chapter-item expanded " > < a href = "../../setup/installation.html" > Installation< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../postgres.html" > Using Postgres< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../reverse_proxy.html" > Configuring a Reverse Proxy< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../setup/forward_proxy.html" > Configuring a Forward/Outbound Proxy< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../turn-howto.html" > Configuring a Turn Server< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../../setup/turn/coturn.html" > coturn TURN server< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../setup/turn/eturnal.html" > eturnal TURN server< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../../delegate.html" > Delegation< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Upgrading< / li > < li class = "chapter-item expanded " > < a href = "../../upgrade.html" > Upgrading between Synapse Versions< / a > < / li > < li class = "chapter-item expanded affix " > < li class = "part-title" > Usage< / li > < li class = "chapter-item expanded " > < a href = "../../federate.html" > Federation< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/index.html" > Configuration< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/config_documentation.html" > Configuration Manual< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/homeserver_sample_config.html" > Homeserver Sample Config File< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/logging_sample_config.html" > Logging Sample Config File< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../structured_logging.html" > Structured Logging< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../templates.html" > Templates< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/user_authentication/index.html" > User Authentication< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/user_authentication/single_sign_on/index.html" > Single-Sign On< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../../openid.html" > OpenID Connect< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/user_authentication/single_sign_on/saml.html" > SAML< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/user_authentication/single_sign_on/cas.html" > CAS< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../sso_mapping_providers.html" > SSO Mapping Providers< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../../password_auth_providers.html" > Password Auth Providers< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../jwt.html" > JSON Web Tokens< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../usage/configuration/user_authentication/refresh_tokens.html" > Refresh Tokens< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../../CAPTCHA_SETUP.html" > Registration Captcha< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../application_services.html" > Application Services< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../server_notices.html" > Server Notices< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../consent_tracking.html" > Consent Tracking< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../user_directory.html" > User Directory< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../message_retention_policies.html" > Message Retention Policies< / a > < / li > < li class = "chapter-item expanded " > < a href = "../../modules/index.html" > Pluggable Modules< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../../modules/writ
2021-12-01 11:12:48 -07:00
< / div >
< div id = "sidebar-resize-handle" class = "sidebar-resize-handle" > < / div >
< / nav >
< div id = "page-wrapper" class = "page-wrapper" >
< div class = "page" >
< div id = "menu-bar-hover-placeholder" > < / div >
< div id = "menu-bar" class = "menu-bar sticky bordered" >
< div class = "left-buttons" >
< button id = "sidebar-toggle" class = "icon-button" type = "button" title = "Toggle Table of Contents" aria-label = "Toggle Table of Contents" aria-controls = "sidebar" >
< i class = "fa fa-bars" > < / i >
< / button >
< button id = "theme-toggle" class = "icon-button" type = "button" title = "Change theme" aria-label = "Change theme" aria-haspopup = "true" aria-expanded = "false" aria-controls = "theme-list" >
< i class = "fa fa-paint-brush" > < / i >
< / button >
< ul id = "theme-list" class = "theme-popup" aria-label = "Themes" role = "menu" >
< li role = "none" > < button role = "menuitem" class = "theme" id = "light" > Light (default)< / button > < / li >
< li role = "none" > < button role = "menuitem" class = "theme" id = "rust" > Rust< / button > < / li >
< li role = "none" > < button role = "menuitem" class = "theme" id = "coal" > Coal< / button > < / li >
< li role = "none" > < button role = "menuitem" class = "theme" id = "navy" > Navy< / button > < / li >
< li role = "none" > < button role = "menuitem" class = "theme" id = "ayu" > Ayu< / button > < / li >
< / ul >
< button id = "search-toggle" class = "icon-button" type = "button" title = "Search. (Shortkey: s)" aria-label = "Toggle Searchbar" aria-expanded = "false" aria-keyshortcuts = "S" aria-controls = "searchbar" >
< i class = "fa fa-search" > < / i >
< / button >
< / div >
< h1 class = "menu-title" > Synapse< / h1 >
< div class = "right-buttons" >
< a href = "../../print.html" title = "Print this book" aria-label = "Print this book" >
< i id = "print-button" class = "fa fa-print" > < / i >
< / a >
< a href = "https://github.com/matrix-org/synapse" title = "Git repository" aria-label = "Git repository" >
< i id = "git-repository-button" class = "fa fa-github" > < / i >
< / a >
< a href = "https://github.com/matrix-org/synapse/edit/develop/docs/usage/administration/useful_sql_for_admins.md" title = "Suggest an edit" aria-label = "Suggest an edit" >
< i id = "git-edit-button" class = "fa fa-edit" > < / i >
< / a >
< / div >
< / div >
< div id = "search-wrapper" class = "hidden" >
< form id = "searchbar-outer" class = "searchbar-outer" >
< input type = "search" id = "searchbar" name = "searchbar" placeholder = "Search this book ..." aria-controls = "searchresults-outer" aria-describedby = "searchresults-header" >
< / form >
< div id = "searchresults-outer" class = "searchresults-outer hidden" >
< div id = "searchresults-header" class = "searchresults-header" > < / div >
< ul id = "searchresults" >
< / ul >
< / div >
< / div >
<!-- Apply ARIA attributes after the sidebar and the sidebar toggle button are added to the DOM -->
< script type = "text/javascript" >
document.getElementById('sidebar-toggle').setAttribute('aria-expanded', sidebar === 'visible');
document.getElementById('sidebar').setAttribute('aria-hidden', sidebar !== 'visible');
Array.from(document.querySelectorAll('#sidebar a')).forEach(function(link) {
link.setAttribute('tabIndex', sidebar === 'visible' ? 0 : -1);
});
< / script >
< div id = "content" class = "content" >
< main >
<!-- Page table of contents -->
< div class = "sidetoc" >
< nav class = "pagetoc" > < / nav >
< / div >
< h2 id = "some-useful-sql-queries-for-synapse-admins" > < a class = "header" href = "#some-useful-sql-queries-for-synapse-admins" > Some useful SQL queries for Synapse Admins< / a > < / h2 >
< h2 id = "size-of-full-matrix-db" > < a class = "header" href = "#size-of-full-matrix-db" > Size of full matrix db< / a > < / h2 >
2022-05-09 15:43:32 -06:00
< pre > < code class = "language-sql" > SELECT pg_size_pretty( pg_database_size( 'matrix' ) );
< / code > < / pre >
2021-12-01 11:12:48 -07:00
< h3 id = "result-example" > < a class = "header" href = "#result-example" > Result example:< / a > < / h3 >
< pre > < code > pg_size_pretty
----------------
6420 MB
(1 row)
< / code > < / pre >
< h2 id = "show-top-20-larger-tables-by-row-count" > < a class = "header" href = "#show-top-20-larger-tables-by-row-count" > Show top 20 larger tables by row count< / a > < / h2 >
2022-05-09 15:43:32 -06:00
< pre > < code class = "language-sql" > SELECT relname, n_live_tup AS " rows"
FROM pg_stat_user_tables
2021-12-01 11:12:48 -07:00
ORDER BY n_live_tup DESC
LIMIT 20;
< / code > < / pre >
2022-05-09 15:43:32 -06:00
< p > This query is quick, but may be very approximate, for exact number of rows use:< / p >
< pre > < code class = "language-sql" > SELECT COUNT(*) FROM < table_name> ;
< / code > < / pre >
2021-12-01 11:12:48 -07:00
< h3 id = "result-example-1" > < a class = "header" href = "#result-example-1" > Result example:< / a > < / h3 >
< pre > < code > state_groups_state - 161687170
event_auth - 8584785
event_edges - 6995633
event_json - 6585916
event_reference_hashes - 6580990
events - 6578879
received_transactions - 5713989
event_to_state_groups - 4873377
stream_ordering_to_exterm - 4136285
current_state_delta_stream - 3770972
event_search - 3670521
state_events - 2845082
room_memberships - 2785854
cache_invalidation_stream - 2448218
state_groups - 1255467
state_group_edges - 1229849
current_state_events - 1222905
users_in_public_rooms - 364059
device_lists_stream - 326903
user_directory_search - 316433
< / code > < / pre >
< h2 id = "show-top-20-larger-tables-by-storage-size" > < a class = "header" href = "#show-top-20-larger-tables-by-storage-size" > Show top 20 larger tables by storage size< / a > < / h2 >
< pre > < code class = "language-sql" > SELECT nspname || '.' || relname AS " relation" ,
2022-05-09 15:43:32 -06:00
pg_size_pretty(pg_total_relation_size(c.oid)) AS " total_size"
FROM pg_class c
LEFT JOIN pg_namespace n ON (n.oid = c.relnamespace)
2021-12-01 11:12:48 -07:00
WHERE nspname NOT IN ('pg_catalog', 'information_schema')
2022-05-09 15:43:32 -06:00
AND c.relkind < > 'i'
2021-12-01 11:12:48 -07:00
AND nspname !~ '^pg_toast'
2022-05-09 15:43:32 -06:00
ORDER BY pg_total_relation_size(c.oid) DESC
2021-12-01 11:12:48 -07:00
LIMIT 20;
< / code > < / pre >
< h3 id = "result-example-2" > < a class = "header" href = "#result-example-2" > Result example:< / a > < / h3 >
< pre > < code > public.state_groups_state - 27 GB
public.event_json - 9855 MB
public.events - 3675 MB
public.event_edges - 3404 MB
public.received_transactions - 2745 MB
public.event_reference_hashes - 1864 MB
public.event_auth - 1775 MB
public.stream_ordering_to_exterm - 1663 MB
public.event_search - 1370 MB
public.room_memberships - 1050 MB
public.event_to_state_groups - 948 MB
public.current_state_delta_stream - 711 MB
public.state_events - 611 MB
public.presence_stream - 530 MB
public.current_state_events - 525 MB
public.cache_invalidation_stream - 466 MB
public.receipts_linearized - 279 MB
public.state_groups - 160 MB
public.device_lists_remote_cache - 124 MB
public.state_group_edges - 122 MB
< / code > < / pre >
2022-05-09 15:43:32 -06:00
< h2 id = "show-top-20-larger-rooms-by-state-events-count" > < a class = "header" href = "#show-top-20-larger-rooms-by-state-events-count" > Show top 20 larger rooms by state events count< / a > < / h2 >
< p > You get the same information when you use the
< a href = "../../admin_api/rooms.html#list-room-api" > admin API< / a >
and set parameter < code > order_by=state_events< / code > .< / p >
< pre > < code class = "language-sql" > SELECT r.name, s.room_id, s.current_state_events
FROM room_stats_current s
LEFT JOIN room_stats_state r USING (room_id)
ORDER BY current_state_events DESC
LIMIT 20;
< / code > < / pre >
< p > and by state_group_events count:< / p >
< pre > < code class = "language-sql" > SELECT rss.name, s.room_id, COUNT(s.room_id)
FROM state_groups_state s
LEFT JOIN room_stats_state rss USING (room_id)
GROUP BY s.room_id, rss.name
ORDER BY COUNT(s.room_id) DESC
LIMIT 20;
< / code > < / pre >
< p > plus same, but with join removed for performance reasons:< / p >
< pre > < code class = "language-sql" > SELECT s.room_id, COUNT(s.room_id)
FROM state_groups_state s
GROUP BY s.room_id
ORDER BY COUNT(s.room_id) DESC
LIMIT 20;
< / code > < / pre >
< h2 id = "show-top-20-rooms-by-new-events-count-in-last-1-day" > < a class = "header" href = "#show-top-20-rooms-by-new-events-count-in-last-1-day" > Show top 20 rooms by new events count in last 1 day:< / a > < / h2 >
< pre > < code class = "language-sql" > SELECT e.room_id, r.name, COUNT(e.event_id) cnt
FROM events e
LEFT JOIN room_stats_state r USING (room_id)
WHERE e.origin_server_ts > = DATE_PART('epoch', NOW() - INTERVAL '1 day') * 1000
GROUP BY e.room_id, r.name
ORDER BY cnt DESC
LIMIT 20;
< / code > < / pre >
< h2 id = "show-top-20-users-on-homeserver-by-sent-events-messages-at-last-month" > < a class = "header" href = "#show-top-20-users-on-homeserver-by-sent-events-messages-at-last-month" > Show top 20 users on homeserver by sent events (messages) at last month:< / a > < / h2 >
< p > Caution. This query does not use any indexes, can be slow and create load on the database.< / p >
< pre > < code class = "language-sql" > SELECT COUNT(*), sender
FROM events
WHERE (type = 'm.room.encrypted' OR type = 'm.room.message')
AND origin_server_ts > = DATE_PART('epoch', NOW() - INTERVAL '1 month') * 1000
GROUP BY sender
ORDER BY COUNT(*) DESC
LIMIT 20;
< / code > < / pre >
< h2 id = "show-last-100-messages-from-needed-user-with-room-names" > < a class = "header" href = "#show-last-100-messages-from-needed-user-with-room-names" > Show last 100 messages from needed user, with room names:< / a > < / h2 >
< pre > < code class = "language-sql" > SELECT e.room_id, r.name, e.event_id, e.type, e.content, j.json
FROM events e
LEFT JOIN event_json j USING (room_id)
LEFT JOIN room_stats_state r USING (room_id)
WHERE sender = '@LOGIN:example.com'
AND e.type = 'm.room.message'
ORDER BY stream_ordering DESC
LIMIT 100;
< / code > < / pre >
2021-12-01 11:12:48 -07:00
< h2 id = "show-rooms-with-names-sorted-by-events-in-this-rooms" > < a class = "header" href = "#show-rooms-with-names-sorted-by-events-in-this-rooms" > Show rooms with names, sorted by events in this rooms< / a > < / h2 >
2022-05-09 15:43:32 -06:00
< p > < strong > Sort and order with bash< / strong > < / p >
< pre > < code class = "language-bash" > echo " SELECT event_json.room_id, room_stats_state.name FROM event_json, room_stats_state \
WHERE room_stats_state.room_id = event_json.room_id" | psql -d synapse -h localhost -U synapse_user -t \
| sort | uniq -c | sort -n
< / code > < / pre >
< p > Documentation for < code > psql< / code > command line parameters: https://www.postgresql.org/docs/current/app-psql.html< / p >
< p > < strong > Sort and order with SQL< / strong > < / p >
< pre > < code class = "language-sql" > SELECT COUNT(*), event_json.room_id, room_stats_state.name
FROM event_json, room_stats_state
WHERE room_stats_state.room_id = event_json.room_id
GROUP BY event_json.room_id, room_stats_state.name
ORDER BY COUNT(*) DESC
LIMIT 50;
< / code > < / pre >
2021-12-01 11:12:48 -07:00
< h3 id = "result-example-3" > < a class = "header" href = "#result-example-3" > Result example:< / a > < / h3 >
< pre > < code > 9459 !FPUfgzXYWTKgIrwKxW:matrix.org | This Week in Matrix
9459 !FPUfgzXYWTKgIrwKxW:matrix.org | This Week in Matrix (TWIM)
17799 !iDIOImbmXxwNngznsa:matrix.org | Linux in Russian
18739 !GnEEPYXUhoaHbkFBNX:matrix.org | Riot Android
23373 !QtykxKocfZaZOUrTwp:matrix.org | Matrix HQ
39504 !gTQfWzbYncrtNrvEkB:matrix.org | ru.[matrix]
43601 !iNmaIQExDMeqdITdHH:matrix.org | Riot
43601 !iNmaIQExDMeqdITdHH:matrix.org | Riot Web/Desktop
< / code > < / pre >
< h2 id = "lookup-room-state-info-by-list-of-room_id" > < a class = "header" href = "#lookup-room-state-info-by-list-of-room_id" > Lookup room state info by list of room_id< / a > < / h2 >
2022-05-09 15:43:32 -06:00
< p > You get the same information when you use the
< a href = "../../admin_api/rooms.html#room-details-api" > admin API< / a > .< / p >
< pre > < code class = "language-sql" > SELECT rss.room_id, rss.name, rss.canonical_alias, rss.topic, rss.encryption,
rsc.joined_members, rsc.local_users_in_room, rss.join_rules
FROM room_stats_state rss
LEFT JOIN room_stats_current rsc USING (room_id)
WHERE room_id IN ( WHERE room_id IN (
'!OGEhHVWSdvArJzumhm:matrix.org',
'!YTvKGNlinIzlkMTVRl:matrix.org'
);
< / code > < / pre >
< h2 id = "show-users-and-devices-that-have-not-been-online-for-a-while" > < a class = "header" href = "#show-users-and-devices-that-have-not-been-online-for-a-while" > Show users and devices that have not been online for a while< / a > < / h2 >
< pre > < code class = "language-sql" > SELECT user_id, device_id, user_agent, TO_TIMESTAMP(last_seen / 1000) AS " last_seen"
FROM devices
WHERE last_seen < DATE_PART('epoch', NOW() - INTERVAL '3 month') * 1000;
2021-12-01 11:12:48 -07:00
< / code > < / pre >
< / main >
< nav class = "nav-wrapper" aria-label = "Page navigation" >
<!-- Mobile navigation buttons -->
< a rel = "prev" href = "../../usage/administration/understanding_synapse_through_grafana_graphs.html" class = "mobile-nav-chapters previous" title = "Previous chapter" aria-label = "Previous chapter" aria-keyshortcuts = "Left" >
< i class = "fa fa-angle-left" > < / i >
< / a >
< a rel = "next" href = "../../usage/administration/database_maintenance_tools.html" class = "mobile-nav-chapters next" title = "Next chapter" aria-label = "Next chapter" aria-keyshortcuts = "Right" >
< i class = "fa fa-angle-right" > < / i >
< / a >
< div style = "clear: both" > < / div >
< / nav >
< / div >
< / div >
< nav class = "nav-wide-wrapper" aria-label = "Page navigation" >
< a rel = "prev" href = "../../usage/administration/understanding_synapse_through_grafana_graphs.html" class = "nav-chapters previous" title = "Previous chapter" aria-label = "Previous chapter" aria-keyshortcuts = "Left" >
< i class = "fa fa-angle-left" > < / i >
< / a >
< a rel = "next" href = "../../usage/administration/database_maintenance_tools.html" class = "nav-chapters next" title = "Next chapter" aria-label = "Next chapter" aria-keyshortcuts = "Right" >
< i class = "fa fa-angle-right" > < / i >
< / a >
< / nav >
< / div >
< script type = "text/javascript" >
window.playground_copyable = true;
< / script >
< script src = "../../elasticlunr.min.js" type = "text/javascript" charset = "utf-8" > < / script >
< script src = "../../mark.min.js" type = "text/javascript" charset = "utf-8" > < / script >
< script src = "../../searcher.js" type = "text/javascript" charset = "utf-8" > < / script >
< script src = "../../clipboard.min.js" type = "text/javascript" charset = "utf-8" > < / script >
< script src = "../../highlight.js" type = "text/javascript" charset = "utf-8" > < / script >
< script src = "../../book.js" type = "text/javascript" charset = "utf-8" > < / script >
<!-- Custom JS scripts -->
< script type = "text/javascript" src = "../../docs/website_files/table-of-contents.js" > < / script >
< / body >
< / html >