This document discusses using the Migrate module in Drupal to migrate content from one version of a Drupal site to another. It covers analyzing legacy data, mapping source and destination fields, writing migration code, and using tools like phpMyAdmin, Devel, and Drush to assist with the migration process. Key aspects of the Migrate module like migration classes, field handlers, and destination handlers are explained.

1. A pain free (sort of)
approach to the
Migraine (aka Migrate)
module.

2. Dennis Solis
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Solis Media Group
Over 20 years of application software development.
Two years of Drupal development
Procedural php coder
Learning OO php
Do not understand the magic of OO
Migraine module helped
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3. My Assignment
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Migrate OA Beta to OA 1.4 on Drupal 6.
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4. Data Migration Options
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Move data by hand
Feeds and Feeds Tamper
Migrate module
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5. Smoothing the Move
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http://denver2012.drupal.org/program/sessions/
migration-smoothing-move
Analyze – understand the legacy data
Map – Line up source fields with destination fields
Iterate – try, try, again – until it works
Congratulations – you done
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6. Feeds
No coding except for special conditions
Setup / execution is done via a UI
LOT easier to setup and use
Comes with a mapping screen.
It is limited
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Receiving module needs to support feeds.
Does not support all fields but you can write code
to handle the fields.
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7. Feeds
Works great
Limited by lack of field handlers
It is a bit slow
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Especially for LOTS of data
Does not work well if
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Different contents types that reference the other.
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8. Feeds Tamper
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Manipulate the data before processing
Works with Feeds
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9. Migrate Module
Import data / contents into Drupal 6, 7, and 8
Migrate for Drupal 6 and 7 are about 95%
compatible
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Drupal 6 – uses dbtng and autoload
Mapping is done in code
Very flexible
Much Faster
Migraine is here to stay.
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It is in Drupal 8 core
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10. Migrate
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Migrate 2.0
New Migrate 7.2-x-dev - – released 10-01-2013
 Migrate 2.0 for D6 requires the autoload and dbtng
modules.
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Migrate d 2 d
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New Migrate 7.2-x-dev – released 10-01-2013
Migrate Extra – Sub-module within Migrate
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11. Migrate D 2 D
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Use this to migrate from 6 to 7 or 8
All the benefits and pain of the migrate module
Provides class specific to older versions of
Drupal.
It does a lot of the work that I had to do manually
 I could not use because I went D6 to D6.
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12. Migrate OG
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Only use if you are using Migrate 1.0
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The Organic Group migration support for
Migrate 2.0 has been moved into Organic
Groups itself.
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13. Drupalcon Denver
Andrew Morton stated the migrate module:
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Two weeks of banging his head
Tricky to get started with
Steep learning curve
Inscrutable
Complex
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14. Learning Cliff
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Open Atrium
Open Atrium Data Structure
Migrate Module
OO Php
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15. My Gifts to You
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How to connect to multiple databases
Easily find the D6 source data structure
How to user the Migration UI
How to write migration code
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16. Ease the pain
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phpMyAdmin
Devel module
Migrate UI
Beer and Wine examples
Drush
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17. phpMyAdmin
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How to read the keys to the tables
Click on the index tab
Database search for data
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18. Open Atrium Structure
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19. OA Data Structure
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Taxonomy
User and User Profile
Organic Group nodes
Books
Content Types
Comments
Case Tracker Data Structure
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20. Tools you will need
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Football helmet
A LOT of aspirins
Patience
Tenacity
A little bit of knowledge
A little OO
 A little migration code
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21. Devel Module
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Devel
Devel node acces
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22. Migrate Module
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Migrate UI
Migrate
Migrate Extras
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23. Other Modules
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dbtng – back ports many of the Drupal 7
database functions back to D 6
autoload – helper module to autoload
classes under PHP 5
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24. OO definitions
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An object is a self-contained component that
contains properties and methods needed to
make a certain type of data useful.
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For example, in a project management application,
you would have a:
Status object
 Cost object
 Client object among others.
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25. OO definitions
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An object’s properties are what it knows. (This
of this as variables related to the object.)
Its methods are what it can do. (This if this as
functions or subroutines.)
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26. OO definitions
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A class is a blueprint or template or set of
instructions to build a specific type of object.
Every object is built from a class. Each class
should be designed and programmed to
accomplish one, and only one, thing.
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27. OO definitions
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An instance is a specific object built from a
specific class. It is assigned to a reference
variable that is used to access all of the instance's
properties and methods. When you make a new
instance the process is called instantiation and
is typically done using the new keyword.
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28. OO definitions
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A class is like a recipe for chocolate cake. The
recipe itself is not a cake. You can't eat the
recipe (or at least wouldn't want to).
If you correctly do what the recipe tells you to
do (instantiate it) then you have an edible cake.
That edible cake is an instance of the chocolate
cake class.
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29. OO concepts
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A class is like a recipe for chocolate cake. The
recipe itself is not a cake. You can't eat the
recipe (or at least wouldn't want to).
If you correctly do what the recipe tells you to
do (instantiate it) then you have an edible cake.
That edible cake is an instance of the chocolate
cake class.
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30. Your Migrate Module
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Migration should be in a SEPARATE
module
So you can turn it off once you are done.
 Isolate it if you are going to be doing ongoing
date based updates.
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31. Migrate supports
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Support multi-field or composite keys.
Tracks the source id and it’s final destination id
and you can access this information during your
migration.
Translate from the old key to the new key.
Can do a roll back.
Can re-do a migration and update those articles
in place.
Do “date” based ongoing migrations.
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32. Migration class
Configure all of your pieces for the migration
 Selects the source data and map it to the
destination data.
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33. Migration class
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prepareRow(), prepare(), complete()
Allow you to manipulate the data or skip records
 Update other rows while migrating data
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Writes out the destination data.
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34. Migration class
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35. Source data
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Source data can be in SQL, CSV, XML, JSON
format
Need to have definition of these files.
I used the SQL format.
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36. Field Handlers
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A field definition within Drupal is an array structure
Converts simple string data into the Drupal array
structure
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37. Destination Handlers
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comments.inc
fields.inc
node.inc
table.inc
term.inc
entity.inc
file.inc
path.inc
table_copy.inc
user.inc
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38. Destination
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Migrate will write the Destination nodes for
you (node, user, other supported entities, or
SQL rows).
Create one destination record for each source
record
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39. Order is critical
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Must migrate user accounts before you can
migrate user profiles.
Know you data
Create a list of the sequence in which the data
is to be converted.
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40. Migration Class
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Everything is done in code
You write a “base class” from which you then
extend in your code. In this base class, you can
define things about this migration.
Everything you want to do is an extension of
an existing migrate class.
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41. Migration Class
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Inherit and extend these classes
You have to write a small module to “extend”
the classes.
Documentation is provided in the form of
code examples.
beer.inc
 wire.inc
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42. Multiple DB in D6
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Database select from within current
database:
*
$db_url = 'pgsql://username:password@localhost/databasename';
*/
*// - das - $db_url = 'mysqli://root@localhost/mis_project';
$db_url['default'] = 'mysqli://root@localhost/mis_project';
$db_url['legacy'] = 'mysqli://root@localhost/open_atrium_legacy';
$db_prefix = '';
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Database select from within current
database:
$query = db_select('users_legacy', 'ul');
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43. Multiple DB in D7
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Define the database
Database::addConnectionInfo('jnn_xoops', 'default', array(
'driver' => 'mysql',
'database' => 'jnn_xoops',
'username' => 'root',
'password' => 'root',
'host' => 'localhost',
'prefix' => '',
));
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Define the query
$query = Database::getConnection('default', 'jnn_xoops')
->select('xoops_users', 'xu')
->fields('xu', array('uid', 'name', 'uname', 'email'));
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44. My Module
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Structure of my migration module was placed in
sites/all/modules/custom.
My module name is: migrate_mc_oa
migrate_mc_oa.info
 migrate_mc_oa.install
 migrate_mc_oa.module
 migrate_mc_oa.inc
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45. My Module
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Structure of my migration module
migrate_mc_oa_user.inc
 migrate_mc_oa_node_og.inc
 migrate_mc_oa_book.inc
 migrate_mc_oa_node_ct.inc
 migrate_mc_oc_comment.inc
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46. My Module
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47. Let’s see the code
class McOaBasicMigration extends McOaMigration {
public function __construct() {
parent::__construct();
$this->description = t('Descriptions');
$this->dependencies = array('Other_Migration_Dependencies');
$this->map = new MigrateSQLMap(....));
$query=db_select('comments_legacy', 'cl');
or
$query = Database::getConnection('default', 'legacy')
->select('comments', 'cl');
$this->source = new MigrateSourceSQL($query);
$this->destination = new MigrateDestinationComment('comment_case_tracker_case');
$this->addFieldMapping('pid', 'pid');
$this->addFieldMapping('nid', 'nid')
->sourceMigration('McOaCaseCt');
// Unmapped destination fields
$this->addUnmigratedDestinations(array('fname', 'lname'));
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48. Drush Migrate Cmds
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https://drupal.org/node/1561820
drush migrate-import Article
drush migrate-import Article --limit="100 items"
drush migrate-import --all=User
drush migrate-import –rollback –all
drush migrate-import –update –group = [grp_name]
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