Скачать или смотреть Salesforce | Apex | SOQL | Governer Limits | DML |Exceptional Statement | Locking Statement

Salesforce Realtime Training Apex Session 06 By Swapna
SOQL : Salesforce Object Query Language:
#SOQL is to built in query string, used to retrive the data from salesforce.

Usage :
1 In the querystring parameter in the query call
2 In Apex Statement
3 In Visualforce Page controller
4 In schema Explorer of the Force.Com IDE
5 Aura Method controller

Syntax:
SELECT API fieldName FROM API Table Name -- Account : 100,000
WHERE Condition
WITH filteration
GROUP BY API fieldName
HAVING Condition
ORDER BY API FieldName
LIMIT NUmber
OFFSET Number

#GovernerLimits: Apex class
Total Number of SOQL queries issued: 100, 200,
Total Number of SOQL records retrived by SOQL query -- 50,000 --
single SOQL -2,000

TIP :
never use the SOQL query inside the loops
never ever use DML inside for loops

8. DML Data Manipulation Language:

: Apex Program that enables developer to perform CRUD Operations Create, retrieve,
update , delete during runtime
: insert , update, delete, retrieve or restore data in database.

2 types of DML statements
Atomic DML
Non-Atomic DML


Atomic DML Non-Atomic DML
DML Statements Database class Methods
insert Database.insert
update Database.update
upsert Database.upsert
delete Database.delete
undelete Database.undelete
merge Database.merge
TIP : Upsert is Data loading /Batch

9.#ExceptionalStatement :
Apex statement, that capture error during the destruction of normal
flow of code execution and takes corrective mesurement
try
catchException e

10. Locking Statement :
Apex statement that locks sobject record from being updated

'For Update' Keyword SOQL

SELECT id,Name From Account where Name='Amazon' For Update