Git commit a1b10cbd64fd35788147aba21324dfd862a24b50 by Swati Lodha. Committed on 01/09/2016 at 12:59. Pushed by swatil into branch 'master'.
Update handbook A +- -- digikam/intro-database-migration.png M +70 -13 digikam/intro-database.docbook http://commits.kde.org/digikam-doc/a1b10cbd64fd35788147aba21324dfd862a24b50 diff --git a/digikam/intro-database-migration.png b/digikam/intro-database-migration.png new file mode 100644 index 0000000..50397b0 Binary files /dev/null and b/digikam/intro-database-migration.png differ diff --git a/digikam/intro-database.docbook b/digikam/intro-database.docbook index f4b4567..0ae44fb 100644 --- a/digikam/intro-database.docbook +++ b/digikam/intro-database.docbook @@ -5,8 +5,8 @@ <title>Introduction</title> <para> - <!-- TODO : explain here why we use database, which information are stored inside, the advantage to search information, - how it's populated, how it's updated, etc...--> + 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> @@ -36,7 +36,7 @@ <title>The Sqlite Database</title> <para> - <!-- TODO : add more description of sqlite as the most use embeded DB in the world --> + SQLite is a relational database management system, contained in C programming library. SQLite is not directly comparable to client/server SQL database engines such as MySQL, Oracle or PostgreSQL. Rather, it is an embedded SQL database engine, i.e. it is embedded in an end program. SQLite reads and writes directly to ordinary disk files.For device-local storage with low writer concurrency and less than a terabyte of content, SQLite is almost always a better solution. SQLite is fast and reliable and it requires no configuration or maintenance. It keeps thing simple. SQLite "just works". </para> <para> @@ -44,7 +44,7 @@ </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, and voila! </para> <note><para> @@ -52,7 +52,7 @@ </para></note> <para> - <!-- TODO : add more details about storage place of sqlite files --> + 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). </para> <para> @@ -70,11 +70,47 @@ <title>MySQL Versus SQLite</title> <para> - <!-- TODO : add more description of Mysqland MAriabd, the history and differences, especially about how many items can be stored in each DB type (items and albums) --> + 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. + </para></listitem> + + <listitem><para> + More cutting edge features. + </para></listitem> + + <listitem><para> + More storage engines. + </para></listitem> + + <listitem><para> + Better performance. + </para></listitem> + + <listitem><para> + 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? 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. + &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. </para> <para> @@ -116,16 +152,16 @@ <title>The MySQL Remote Server</title> <para> - Obviously, to use &digikam; with a remote MySQL, you would require a MySQL server. Or, you could also install MariaDB, which serves the purpose well. (Could be installed easily using this <ulink url="http://www.liquidweb.com/kb/how-to-install-mariadb-5-5-on-ubuntu-14-04-lts/";>link</ulink>.) + Obviously, to use &digikam; with a remote MySQL, you would require a MySQL server. Or, you could also install MariaDB, which serves the purpose well. (Could be installed easily using this <ulink url="http://www.liquidweb.com/kb/how-to-install-mariadb-5-5-on-ubuntu-14-04-lts/";>link</ulink>.) </para> <para> Follow the instructions below, if you don’t have a dedicated user account and a &digikam; database already set up. Run the commands in MySQL server (after replacing password with correct one): </para> - <para> - <!-- TODO : The instruction below are not enough as command arguments will chnage depending of database names --> - </para> + <note><para> + You can select any database name. (Here it is, “digikam”). Just remember to fill in the database name correctly in Core, Thumbs, Face Db Name in the dialog box shown below. + </para></note> <blockquote><screen> CREATE USER ''@'%' IDENTIFIED BY 'password'; @@ -163,8 +199,29 @@ <!-- TODO : add new sect2 about Database backup recommendation --> - <!-- TODO : add new sect2 about Database migration tool --> - + <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: + </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> <!--
