<div class="left"><p><strong>About the Structured Query Language (SQL)...</strong><br /><br />SQL commands are mainly categorized into four categories as:</p><p><strong>DDL</strong>:&nbsp; Data Definition Language<br /><strong>DQL</strong>:&nbsp; Data Query Language<br /><strong>DML</strong>:<strong>&nbsp; </strong>Data Manipulation Language<br /><strong>DCL</strong>:&nbsp; Data Control Language<br />&nbsp;</p><ol start="1" style="list-style-type: lower-alpha;"> <li>DDL creates the tables with the required columns and with corect data types (numbers; dates; text strings; etc.)<br /> &nbsp;</li> <li>DQL&nbsp;reads from one or more rows of one or more tables in the&nbsp;database.<br /> &nbsp;</li> <li>DML writes a <u>new</u> row (<u>insert</u>) to one or more tables in the database or <u>update</u>s existing fields in one more rows of a table. DML can also <u>delete</u> one or more rows in a table in the database.<br /> &nbsp;</li> <li>DCL authorizes (<u>grants</u>) the database user to perform DDL; DQL or DML operations or <u>revoke</u> the database user&#39;s privileges to perform database operations.</li></ol><p><br />SQL is a common database language used in many Relational Database Management Systems (RDBMS)&nbsp;but it has a lot of dialects.<br /><br /><a href="https://en.wikipedia.org/wiki/SQL-92" target="_blank">SQL-92</a> statements are interpreted by most RDBMS.<br /><br /><a href="https://en.wikipedia.org/wiki/SQL" target="_blank">Read more about SQL here</a>...&nbsp;&nbsp;<br /><br />&nbsp;</p></div><div class="main"><span style="font-size:24px;">Selecting the right database definition file during </span><span style="font-size:24px;">installation</span><br />n-gen.net CMS offers all database table definitions and initial data compiled into one .sql file.<br /><br /><span style="font-size:20px;"><span style="color:#339900;"><u><span style="background-color:#ffff00;">If you are in doubt you should select the newest&nbsp;<span style="font-family:Courier New;Courier;monospace;"> </span></span><span style="font-family:Courier New;Courier;monospace;"><strong><span style="background-color:#ffff00;">install[</span><span style="background-color:#ffff00;">yyyy</span><span style="background-color:#ffff00;">-MM-dd].</span><span style="background-color:#ffff00;">sql</span></strong></span><strong><span style="background-color:#ffff00;">&nbsp; </span></strong><span style="background-color:#ffff00;">file</span></u><span style="background-color:#ffff00;">!</span></span></span><br /><br />Typically the installation files follow these naming conventions:<p><span style="font-family:Courier New;Courier;monospace;"><strong>? install[yyyy-MM-dd].sql =&gt; </strong></span>an SQL-file that contains all you need for installing n-gen.net CMS;<br />&nbsp;&nbsp;&nbsp; i.e. <strong><span style="font-family:Courier New;Courier;monospace;">install[2020-06-06].sql</span></strong><br /><span style="font-family:Courier New;Courier;monospace;"><strong>? install_addXXX[yyyy-MM-dd].sql </strong></span> =&gt; an SQL-file that contains new tables to be added to the database.<br /><br /><br /><img alt="" src="/images/install/SQLcommands.png" style="width: 100%; height: 79%;" /></p></div>

Last updated 25-10-2020 16:41:00