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SQL Commands

Create
Alter
Drop
Truncate
Rename

Select

Insert
Update
Delete
Insert all
Merge

Grant
Revoke

Commit
Rollback
Savepoint

SQL Core Topics

Oracle Keywords
Oracle Reserve Words
Oracle Datatypes
Oracle Clauses
Oracle Functions
Oracle Constraints
Oracle Group By
Oracle JOINS
Oracle Set Operators
Oracle Sub-Queries
Oracle Metadata

Inline Views
Scalar Queries
Types of Tables
Order of Execution
Clauses in Oracle
Cube and RollUp

SQL Advance Topics

Database Transactions
Database Security
Oracle Sequences
Oracle Indexes
Oracle Synonyms
Oracle Clusters

SQL Syntaxes

Delete Rules
Update Rules

Primary Key & Foreign Key relationship

SQL Objects

Tables
Views
Synonyms
Indexes
Clusters
Materialized Views
Types
Sequences
Procedures
Functions
Packages
Triggers

Clauses in Oracle

SELECT
WHERE
ORDER BY
DISTINCT
GROUP BY
HAVING
CONNECT BY PRIOR
START WITH
ON
USING
RETURNING
FOLLOWS

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SQL Order of Execution

FROM
WHERE
GROUP BY
HAVING
SELECT
ORDER BY

Example:
Select empno, ename
FROM emp
WHERE sal > 1000
ORDER BY deptno

Note: First, From clause is executed. i.e Table 'Emp' is loaded.
Second, WHERE clause is executed. i.e Employees whose sal > 1000 are selected.
Third, SELECT clause is executed.i.e Only empno, ename are selected.
Fourth, Order By clause is executed. i.e Sorted by deptno in Ascending Order.

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