Database.QueryLocator object when you are using a simple query (SELECT) to generate the scope of objects used in the batch job. If you use a querylocator object, the governor limit for the total number of records retrieved by SOQL queries is bypassed but we can retrieve up to 10,000 records.
What is difference between database query and database QueryLocator?
Database. getQueryLocator() returns a Query Locator that runs the selected SOQL query returning list that can be iterated over in batch apex and Visualforce page. We can retrieve up to 10,000 records. We can’t use getQueryLocator with any query that contains an aggregate function.
What is the use of QueryLocator?
QueryLocator object. This is useful
when testing the start method
. Returns a new instance of a query locator iterator.
What is database getQueryLocator and what are its advantages?
database.getQueryLocator
returns a Query Locator that runs your selected SOQL query returning list that can be iterated over in bathc apex
or used for displaying large sets in VF (allowing things such as pagination).
What is the difference between database QueryLocator and iterable in Salesforce?
QueryLocator is used when the scope is directly taken from a SOQL. QueryLocator 50 Million can be returned records. Iterable<sObject>:
Governor limits will be enforced
.
What is database query in Salesforce?
database.query in Salesforce allows
you to make a dynamic SOQL query at runtime
. You can build up a string and then use that as a query string at run time in the database.query statement to make a SOQL call that is determined at run time.
Why do we use database queries?
A database query is a
request to access data from a database to manipulate it or retrieve it
. This allows us to perform logic with the information we get in response to the query.
What is database Batchablecontext?
Represents
the parameter type of a batch job method and contains the batch job ID
. This interface is implemented internally by Apex.
What is database stateful?
60. The only time you need Database. Stateful is
when the execute method modifies a class variable in a way meant to be used across multiple execute methods or in the finish method
. The majority of batches you will ever write will not need Database.
What is a QueryLocator in Salesforce?
Database.getQueryLocator in Salesforce
returns a Query Locator that runs your selected SOQL query returning list
that can be iterated over in batch apex or used for displaying large sets in VF. Thanks.
What does a database contain?
A database is an organized collection
of structured information, or data
, typically stored electronically in a computer system. … The data can then be easily accessed, managed, modified, updated, controlled, and organized. Most databases use structured query language (SQL) for writing and querying data.
How do I use a database query in Salesforce?
- Return a single sObject when the query returns a single record: sObject s = Database. …
- Return a list of sObjects when the query returns more than a single record: List<sObject> sobjList = Database.
What is SOSL in Salesforce?
Salesforce Object Search Language
(SOSL) is a Salesforce search language that is used to perform text searches in records. Use SOSL to search fields across multiple standard and custom object records in Salesforce. SOSL is similar to Apache Lucene.
What is iterator in Salesforce?
An iterator
traverses through every item in a collection
. For example, in a while loop in Apex, you define a condition for exiting the loop, and you must provide some means of traversing the collection, that is, an iterator. … Iterators can also be used if you have multiple SELECT statements.
What is meant by iterable in Salesforce?
If you use an iterable,
the governor limit for the total number of records retrieved by SOQL queries is still enforced
. If your code accesses external objects and is used in batch Apex, use Iterable<sObject> instead of Database.
What are governing limits in Salesforce?
| Overview Governor Limit | Total number of SOSL queries issued in Salesforce 20 | DML Governor Limits in Salesforce (Total number of issued statements per transaction) 150 | Total number of records retrieved by a single SOSL query 2000 | Total number of records that were retrieved by SOQL queries 50000 |
|---|
