Custom Setting in Salesforce and Their Importance

Hello Avnish,

Custom settings are similar to custom objects and enable application developers to create custom sets of data, as well as create and associate custom data for an organization, profile, or specific user. All custom settings data is exposed in the application cache, which enables efficient access without the cost of repeated queries to the database. This data can then be used by formula fields, validation rules, flows, Apex, and the SOAP API.

Hi,

Custom settings are similar to custom objects and enable application developers to create custom sets of data, as well as create and associate custom data for an organization, profile, or specific user. Custom Settings are persisted in the database. However they're also cached.When using the cache methods Custom_setting__c.getAll(), .getInstance(), and .getValues(), Salesforce uses the cached values.If you use a SOQL query (SELECT id, name, etc FROM Custom_setting__c) to get data for a custom setting, Salesforce queries the database and uses one of your allotted queries.

NOTE: I've found that you can only consistently modify a custom setting if you use a SOQL query to load it. Loading via a cache method does not load the custom setting's id which is required to update the custom setting.

Accessing a Hierarchy Custom Setting
The following example uses the getOrgDefaults method to return the data set values for the organization level:

CustomSettingName__c mc = CustomSettingName__c.getOrgDefaults();
The following example uses the getInstance method to return the data set values for the specified profile. The getInstancemethod can also be used with a user ID.

CustomSettingName__c mc = CustomSettingName__c.getInstance(Profile_ID);

Accessing a List Custom Setting
The following example returns a map of custom settings data. The getAll method returns values for all custom fields associated with the list setting.

Map<String_dataset_name, CustomSettingName__c> mcs = CustomSettingName__c.getAll();
The following example uses the getValues method to return all the field values associated with the specified data set. This method can be used with both list and hierarchy custom settings, using different parameters.

CustomSettingName__c mc = CustomSettingName__c.getValues(data_set_name);

Hope this helps!