Git commit 65200bfb0d41fed2d20214d70b2e91e1f7e29d99 by Gilles Caulier. Committed on 01/09/2016 at 14:28. Pushed by cgilles into branch 'master'.
polish M +51 -30 digikam/intro-database.docbook http://commits.kde.org/digikam-doc/65200bfb0d41fed2d20214d70b2e91e1f7e29d99 diff --git a/digikam/intro-database.docbook b/digikam/intro-database.docbook index 0ae44fb..0fed6f6 100644 --- a/digikam/intro-database.docbook +++ b/digikam/intro-database.docbook @@ -5,11 +5,12 @@ <title>Introduction</title> <para> - Everyone knows about database, it is used to store data. As all other application programs, DigiKam too uses the database for some obvious reasons like avoiding data duplication, reducing data redundancy and greater data integrity. Moreover, the cost of data entry, storage and retrieval are drastically reduced. Additionally, any user can access the data using query language. - Talking in particular about DigiKam, the Albums, Album Roots, Tags, Thumbnails, Face Recognition Data, Image Metadata, File Paths, Settings etc. are all stored in database. + Everyone knows about database, it is used to store data. As all other application programs, &digikam; too uses the database for some obvious reasons like avoiding data duplication, reducing data redundancy and greater data integrity. Moreover, the cost of data entry, storage and retrieval are drastically reduced. Additionally, any user can access the data using query language. + Talking in particular about &digikam;, the Albums, Album Roots, Tags, Thumbnails, Face Recognition Data, Image Metadata, File Paths, Settings etc. are all stored in database. </para> <para> + The &digikam; actually manages more than one databases. For convenience, it is broadly categorized in three: <orderedlist> @@ -19,7 +20,7 @@ </para></listitem> <listitem><para> - Thumbnails database for compressed thumbnails &ie; to host image thumbs with wavelets compression images. + Thumbnails database for compressed thumbnails &ie; to host image thumbs with wavelets compression images (PGF format). </para></listitem> <listitem><para> @@ -40,11 +41,28 @@ </para> <para> - By default, &digikam; uses SQLite as its back-end for storing important metadata and thumbnails. Three SQLite files used for storing them are digikam4.db, thumbnails-digikam.db, and recognition.db respectively. + By default, &digikam; uses SQLite as its back-end for storing important metadata and thumbnails. Three SQLite files used for storing them are named respectively: + + <orderedlist> + + <listitem><para> + Core: digikam4.db. + </para></listitem> + + <listitem><para> + Thumbs: thumbnails-digikam.db. + </para></listitem> + + <listitem><para> + Faces: recognition.db. + </para></listitem> + + </orderedlist> + </para> <para> - To make your application run fast and smoothly, it is recommended to check and optimize your databases once in awhile. This could be achieved using sqlite3 packages or sqlite browser (high quality, easy to use visual tool for managing database objects). For Ubuntu and its derivatives, it could be retrieved using <command>sudo apt-get install sqlite3</command> or <command>sudo apt-get install sqlitebrowser</command>. Now all remains is to open the terminal, switch to the directory where databases and stored, and voila! + To make your application run fast and smoothly, it is recommended to check and optimize your databases once in awhile. This could be achieved using sqlite3 packages or sqlite browser (high quality, easy to use visual tool for managing database objects). For Ubuntu and its derivatives, it could be retrieved using <command>sudo apt-get install sqlite3</command> or <command>sudo apt-get install sqlitebrowser</command>. Now all remains is to open the terminal, switch to the directory where databases and stored. </para> <note><para> @@ -52,7 +70,7 @@ </para></note> <para> - SQLite database files could be found in your “collection” folder, which you have added to digiKam. (By default, if you add your “Pictures” collection, the DB files will be present in home/Pictures folder). + SQLite database files could be found in your “collection” folder, which you have added to digiKam. (By default, if you add your “Pictures” collection, the DB files will be present in ~/Pictures folder). </para> <para> @@ -73,44 +91,47 @@ MySQL is an open-source, relational database management system, written in C and C++. Original development of MySQL by Michael Widenius and David Axmark beginning in 1994. Sun Microsystems acquired MySQL in 2008, which was later acquired by Oracle in 2010. MySQL currently works on almost all system platforms (Linux, Microsoft Windows, OS X, SunOS …). </para> - + <para> MariaDB server is a community developed fork of MySQL server. Started by core members of the original MySQL team, MariaDB actively works with outside developers to deliver the most featureful, stable, and sanely licensed open SQL server in the industry. </para> - + <para> + MariaDB has actually overtaken MySQL, ‘cause of few basic reasons: + <orderedlist> - + <listitem><para> - MariaDB development is more open and vibrant. + MariaDB development is more open and vibrant. </para></listitem> - + <listitem><para> - More cutting edge features. + More cutting edge features. </para></listitem> - + <listitem><para> - More storage engines. + More storage engines. </para></listitem> - + <listitem><para> - Better performance. + Better performance. </para></listitem> - + <listitem><para> - Compatible and easy to migrate. + Compatible and easy to migrate. </para></listitem> + </orderedlist> + </para> - <para> - &digikam; also provides support for popular MySQL database engine. Of course, you might wonder why you’d want to switch to MySQL when SQLite already does a good job of managing the data? MySQL offers many advantages for storing digiKam data, especially when collections include more than 100,000 items. With such large collections, SQLite introduces latency which slows down the application. + &digikam; also provides support for popular MySQL database engine. Of course, you might wonder why you’d want to switch to MySQL when SQLite already does a good job of managing the data? MySQL offers many advantages for storing &digikam; data, especially when collections include more than 100,000 items. With such large collections, SQLite introduces latency which slows down the application. </para> - + <para> - Using MySQL as digiKam’s database back-end allows you to store the data on local as well as remote server. Local, to replace the local SQLite storage and latter, to use a shared computer through network. Using MySQL as &digikam;’s database back-end allows you to store the data on a remote server. This way, you can use multiple &digikam; installations (⪚ On your notebook and PC) to access and manage your photo collections. You can also use MySQL tools to backup and analyze &digikam;’s data. + Using MySQL as &digikam;’s database back-end allows you to store the data on local as well as remote server. Local, to replace the local SQLite storage and latter, to use a shared computer through network. Using MySQL as &digikam;’s database back-end allows you to store the data on a remote server. This way, you can use multiple &digikam; installations (⪚ On your notebook and PC) to access and manage your photo collections. You can also use MySQL tools to backup and analyze &digikam;’s data. </para> <para> @@ -197,31 +218,31 @@ </sect2> - <!-- TODO : add new sect2 about Database backup recommendation --> + <!-- TODO : add new sect2 about Database backup/maintenance recommendations --> <sect2 id="intro-database-migration"> <title>Database Migration</title> - + <para> The photo management application comes up with an exclusive tool “Database Migration”, that allows users to migrate their data. Suppose, you’re using SQLite and you wish to move all data to MySQL database, migration tool will help you do so. It can help you migrate data from SQLite to MySQL and vice versa. </para> - + <para> - To migrate to another database, go to <guimenu>Settings</guimenu> | <guimenuitem>Migration</guimenuitem> . A dialog box appears: + To migrate to another database, go to <guimenu>Settings</guimenu> | <guimenuitem>Migration</guimenuitem>. A dialog box appears: </para> - + <para> <inlinemediaobject><imageobject> <imagedata fileref="&path;intro-database-migration.png" format="PNG" /></imageobject> </inlinemediaobject> </para> - + <para> Now choose appropriate database types you want to convert to. Finally, click on <guibutton>Migrate</guibutton> button to convert the database from SQLite to MySQL (or vice versa). </para> - + </sect2> - + </sect1> <!--
