jamiechong

Export 2 Multisite exports your standalone database SQL for import into a WP multisite installation. It handles duplicate users (based on email) and will copy over all site settings including Widgets and Menus. You still need to copy the files for your themes, plugins and uploads.
<ul>
<li>This plugin has been minimally tested, but has been used to successfully migrate a handful of standalone sites to a multisite installation.</li>
<li>There is a good possibility it won’t work for sites that make use of a multitude of plugins – especially plugins that have their own database tables.</li>
</ul>
Installation
<ol>
<li>Create a new site on the Multisite.</li>
<li>Copy the plugins and themes from this standalone site to the Multisite.</li>
<li>Copy the files from wp-content/uploads/ on this site to wp-content/uploads/sites// on the multisite.</li>
<li>Backup the database on the Multisite.</li>
<li>Provide the Site ID of the Multisite. This can be found by hovering the mouse over the new site on Network Admin->Sites.</li>
<li>Provide the New URL. Example: //mysite.my-wp-multisite.com</li>
<li>Provide the New file path (The file path of the Multisite installation).</li>
<li>Export the database dump.</li>
<li>Import the SQL into your Multisite installation.</li>
</ol>
<ul>
<li>Important: The exported SQL will DROP the tables that were created for the Site ID you provided. So only perform this migration on new empty Sites.</li>
<li>Note that the you may need to review the exported SQL to ensure that plugin database tables have been exported correctly.</li>
<li>The site admin (username and password) is the user you created while creating the new Site, NOT the site admin of this standalone site.</li>
<li>The guts of this export plugin were inspired by <a href="https://iandunn.name/comprehensive-wordpress-multisite-migrations/" rel="nofollow ugc">this blog post</a></li>
<li>The code for this plugin has been modified from the <a href="https://wordpress.org/plugins/wp-migrate-db" rel="ugc">WP Migrate DB</a> plugin, but should not conflict with it in any way.</li>
</ul>

Export 2 Multisite

Exports your standalone database SQL for import into a WP Multisite installation.

WordPress database is easy to use with simple, but if you want to handle the data that does not conform to the provided initial table structure, or considering the use of as the CMS, you should create a newly table as a better case.
This plugin provides the ability to be able to add a new table freely in the database (direct on MySQL) of WordPress in such a case, and can be management of data in a simple user interface. However, since the plugin version 2.x, you need to be PHP version 5.4 or more on the environment.
When you use the various shortcodes, built-in methods, and APIs that is provided a rich on this plugin, WordPress might be transformed into a powerful CMS.
<a href="https://ka2.org/cdbt/" rel="nofollow ugc">Please see here for more documentation of the plugin</a>. 
All official development on this plugin is on GitHub. Published version will bump here on WordPress.org. You can find the repository at <a href="https://github.com/ka215/cdbt" rel="nofollow ugc">https://github.com/ka215/cdbt</a>.
Detailed documentation has published at the site of author. If you are free, Please try to qv.
<ul>
<li><a href="https://ka2.org/cdbt/v2/" rel="nofollow ugc">Version 2.x related documentation</a></li>
<li><a href="https://ka2.org/cdbt/v1/" rel="nofollow ugc">Version 1.x related documentation</a></li>
</ul>
(Sorry, for about documentation will be only the Japanese version currently.)

Custom DataBase Tables

Hi,
I am using Custom DataBase Tables plugin to create custom tables in database. Its really great. I need to create a password field which needs to be md5 encrypted. how can we do that in this plugin.

password field in table

Using this database management tool, You can create freely own table in  MySQL database, and do input and output of data in an intuitive operation.

Export 2 Multisite vs Custom DataBase Tables