Coding

Views Bulk Operations come handy when doing bulk operations over a selected list. This is great because it combines the power of views to filter the selection and specific actions to do on each selected entity. For Ex: Updating some field in the record, deleting selected entity and so on.

Views also provide an easier way to define your own set of custom functions to perform on each selected row of entities.

First, we need to define an action :

Search for drupal_set_time_limit in Drupal directory and modify the line as below. Ensure that it is restored later once the required operation is over:
For example: Modify the following line in locale.inc file in includes/locale.inc.

<?php
drupal_set_time_limit(240); 
?>

and set to 1800.

There are multiple methods for getting current URL parameters. The following seem to work fine.

filter_input — Gets a specific external variable by name and optionally filters it . Works on PHP 5 >= 5.2.0.

The following code gets the districts from the url provided in the parameter field_district_ref_nid. The filter input converts the result into an array.

Both l and url methods are handy to create urls for various entities. However, the variety of options available makes the usage exciting and complex.

l(): Formats an internal or external URL link as an HTML anchor tag.
Syntax: l($text, $path, array $options = array())

Creating an absolute URL using l(). The example below creates a node link.

This can be achieved using hook_node_view

We may want to get the options available for a field in content type. This can be achieved using Field API.

This post will illustrate various handy file operations available in Drupal

Get Absolute Path of a file from URI : drupal_realpath()
A URI in drupal looks like: private://donor_registration/somefile.csv for a private file
Absolute Path: /srv/www/example.com/public_html/sites/default/private/files/donor_registration/somefile.csv

There are times when we would want to create similar data structures across multiple drupal sites for common functionalities. Although this can be done using features but when the effort involves one time exercise and involves just few fields to be exported, using custom code for creating export definitions for importing in the other site can be a simpler alternative.

If you want export a field definition, you can use the handy field_info_field and field_info_instance functions. Taking our example above, here's how you would call these two functions:

Drupals internal batch API can be really helpful for handling large cumbersome processes on your web server. Rather than submitting a form and waiting for one of these processes to finish before reaching the next page, the batch API can be utilized to break the process down across multiple page loads. This not only cuts down on the server load, but will prevent the page from timing out. Progress bars will be displayed to the user while the process runs which will keep them informed of where they are at in the process.

The purpose is to modify the integer field which captures temperature in decimal.

A good way is to execute a hook_update_N() API in custom module which allows incremental updates when installing, or visiting update.php
WARNING: Does not work. Its better to recreate field after copying data to another temp field.
[ http://drupal.stackexchange.com/questions/103157/modifying-integer-field... ]