koffice/doc/kexi/building.docbook

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  <!DOCTYPE chapter PUBLIC "-//KDE//DTD DocBook XML V4.2-Based Variant V1.1//EN" "dtd/kdex.dtd" >
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<chapter id="building-databases">
<title>Building Simple Databases</title>
<sect1 id="building-intro">
<title>Introduction</title>
<para>
To learn the basics of &kexi;, you could build a simple database
utilizing most elementary &kexi;'s features. To make things simpler,
advanced database design topics will not be covered here.
</para>
<para>
Start by creating a new empty <emphasis>Phone Book</emphasis>.
<!--
See chapter <a href="04_03_00_creating_database.html">4.3.
Creating a new database project</a> for information how to do this.
-->
</para>

<para>Having a new empty database project, perform the following steps:</para>
<procedure>
<step><para>Design database tables. Read <xref linkend="designing-tables"/>.</para></step>
<step><para>Enter data into tables. Read <xref linkend="entering-data-into-tables"/>.</para></step>
<step><para>Design database queries. Read <xref linkend="designing-queries"/>.</para></step>
<step><para>Design forms. Read <xref linkend="designing-forms"/>.</para></step>
<step><para>Use forms to enter data. Read <xref linkend="entering-data-using-forms"/>.</para></step>
</procedure>
</sect1>

<sect1 id="designing-tables">
<title>Designing Database Tables</title>
<para>
First, there will be two tables added to your database:
<emphasis>persons</emphasis> and <emphasis>phone_numbers</emphasis>.
These are exactly the same tables as described in chapter <link
linkend="database-and-spreadsheet">Database and spreadsheet</link>.
A layout for <emphasis>Persons</emphasis> can be found in section
<link linkend="data-integrity-and-validity">Data integrity and validity</link>
in that chapter.
</para>

<procedure>
<step>
<para>
Select <menuchoice><guimenu>Insert</guimenu><guimenuitem>Table</guimenuitem>
</menuchoice> from the Menubar. You can also use the button <guilabel>Create
object: table</guilabel> on the <link linkend="project-navigator-pane">Project
Navigator's toolbar</link>.
</para>
</step>
<step>
<para>
The Table Designer's window will appear. Looking at the top of designer's window
you will notice that &kexi; proposed you a generic name like
<emphasis>template</emphasis> for the new table. The table design is not saved
yet so you will be able to assign more proper name later. Moreover, because of
the same reason, the table name is not yet visible in the
<link linkend="project-navigator-pane">Project Navigator</link>.
</para>
</step>
</procedure>


<sect2 id="design-window">
<title>The Table Designer window</title>
<itemizedlist>
<title>Table Designer window consists of following columns:</title>
<listitem><para>
<guilabel>PK</guilabel> - Primary Key. <!-- It will be discussed this topic in
<link linkend="building-advanced-database">in a later chapter</link>. -->
</para></listitem>
<listitem><para>
<guilabel>Field Caption</guilabel> - caption of the field 
which will be displayed during data entering.
</para></listitem>
<listitem><para>
<guilabel>Data Type</guilabel> - a combo box containing a list of data types,
allowing to set a main rule for entered data for a given field. For example,
when an integer number data type is set for a field, a database user will not
able to enter letter characters into this field.
</para></listitem>
<listitem><para>
<guilabel>Comments</guilabel> - you can enter here any information useful for
understanding what the given field is provided for. This additional text will
be saved within the table design and only visible in design mode.
</para></listitem>
</itemizedlist>
<para>
In the <guilabel>Table designer</guilabel> window, every row corresponds to
a single table field. You can recognize you are in <emphasis>design
mode</emphasis> because the <!-- <img src="icons/state_edit.png" class="icon"> -->
<guibutton>Switch to Design View mode</guibutton> button is toggled on within
the main &kexi; toolbar.
</para>


<procedure>
<title>Designing the <emphasis>Persons</emphasis> table</title>
<step><para>
In the first row click on the cell in the <guilabel>Field Caption</guilabel>
column and enter <emphasis>Name</emphasis> as field caption.
</para>
<itemizedlist>
<title>Notes about field names and captions</title>
<listitem><para>
Every table field must have a name and a caption, these cannot be empty.
</para></listitem>
<listitem><para>
Field name is a word used by the database, usually not visible for users of the database application. The name may not contain special (national) characters (like ±, ¶, Ü)
or space characters. The name must only contain roman letters,
<!-- JSTANIEK: TODO: what about for example japanese letters? Are they allowed in japanese versions?-->
numbers and underscore sign &quot;_&quot;. Use the latter instead of
spaces or dashes.
</para></listitem>
<listitem><para>
Field names must be started with a letter or underscore sign
&quot;_&quot;, never with a number.
</para></listitem>
<listitem><para>
It does not matter whether you are using small or capital letters.
For &kexi; the database name &quot;Persons&quot; is the same as
&quot;persons&quot;.
</para></listitem>
<listitem><para>
Field caption, on the other hand, allows you to enter any letters and special characters. It will be displayed for users of the database application. 
</para></listitem>
</itemizedlist>
</step>

<step>
<itemizedlist>
<title>In a similar way, enter the following fields into the table design:</title>
<listitem><para><guilabel>surname</guilabel></para></listitem>
<listitem><para>street</para></listitem>
<listitem><para>house_number</para></listitem>
<listitem><para>city</para></listitem>
</itemizedlist>
</step>

<step><para>
All the above fields, except <emphasis>house_number</emphasis>, are of type
<emphasis>text</emphasis>.
Change <emphasis>house_number</emphasis> field's type to <emphasis>integer
number</emphasis>. To do this, click on a cell in the <guilabel>Data
Type</guilabel> column, <emphasis>house_number</emphasis> row and then
click on drop down list's button <!--<img src="icons/dropdown_button.png" class="icon">-->
(you can also press <keycombo><keycap>F4</keycap></keycombo> or
<keycombo action="simul">&Alt;<keycap>Down</keycap></keycombo>. The list
of data types will appear. Select the <emphasis>Integer number</emphasis> type.
<!--
 <br><img src="img/05_01_01_changing_datatype.png">
 <br>Changing data type of a filed to integer number<br><br>
-->
</para><para>
From now on, the <emphasis>house_number</emphasis> field only accepts numbers.
</para></step>

<!-- TODO setting additional properties: e.g. caption -->
<step><para>
<emphasis>Persons</emphasis> table design is ready. Click <!-- <img src="icons/state_data.png" class="icon">-->
<guibutton>Switch to Data View</guibutton> button on the toolbar to finish
designing and switch to Data View for the table. This allows you entering
data into the table.
</para></step>

<step><para>
As the design is not yet saved in the database, the <guibutton>Save Object As</guibutton> 
dialog window appears. You need to specify the name for the new table.
<!--
 <br><img src="img/05_01_01_entering_table_name.png">
 <br>Entering table name before saving its design<br><br>
-->
</para>
<para>
&kexi; offers a generic name like <emphasis>Table1</emphasis>.
To change the name, enter <emphasis>Persons</emphasis> into the
<emphasis>Caption</emphasis> field and press the <keycombo>
<keycap>Enter</keycap></keycombo> key or click the <guibutton>OK</guibutton>
button. The <guilabel>Caption</guilabel> field will be used to display the
table to database end-users, &eg; as a form. Unlike the name, the caption can
contain any characters including spaces and special characters.
</para>
<para>
Note that filling the <guilabel>Caption</guilabel> field automatically fills
the <guilabel>Name</guilabel> field. For your convenience the rule for using
only letters, numbers and the &quot;_&quot; character is kept. You
can alter the contents of the <guilabel>Name</guilabel> field if you want to.
<!--
 <br><img src="img/05_01_01_automatic_names.png">
 <br>Example of automatically filled Name field<br><br>
-->
</para></step>

<step><para>
You are asked about an agreement for automatic adding of primary key to the table.
<!--The idea of primary keys is described in <a href=""> -->
<!-- TODO chapter # chapter 6</a>.--> Click <guibutton>Add primary key</guibutton>
button to continue.
<!--
 <br><img src="img/05_01_01_pkey_recommended.png">
 <br>A question about automatic adding a primary key<br><br>
-->
</para></step>

<step><para>
The <emphasis>Persons</emphasis> table has been created and opened in Data View.
Its name appears in the <guilabel>Project Navigator</guilabel> pane.
<!-- <br><img src="img/05_01_01_table_created.png">
 <br><em>Persons</em> table in the Project Navigator pane<br><br>
-->
</para></step>

<step><para>
Create the <emphasis>phone_numbers</emphasis> table, in a similar
way as <emphasis>persons</emphasis> table.
</para></step>

<step><para>
Create a <emphasis>person</emphasis> field of type <emphasis>Integer
number</emphasis> and <emphasis>phone</emphasis> of type <emphasis>Text</emphasis>.
Do not use a number type here because phone numbers can have many different
forms and prefixes.
</para></step>

<step><para>
Click <!--<img src="icons/state_data.png" class="icon"> --> <guibutton>Switch to
Data View</guibutton> button on the toolbar and enter <emphasis>Phones</emphasis>
caption for the table. As for your previous table, allow &kexi; to automatically
create a primary key.
</para></step>
</procedure>

</sect2>

</sect1>

&enteringdataintotables;

&querydesigning;

&designingforms;

&enteringdatausingforms;

</chapter>