Oracle Database – Querying

This 12-hour course is designed to provide participants with a comprehensive understanding of querying Oracle databases using SQL. The course covers fundamental SQL concepts, advanced querying techniques, and performance optimization strategies specific to Oracle. By the end of the course, students will be able to efficiently retrieve and manipulate data in an Oracle database environment.

Introduction to Oracle SQL and SQL Basics

• Overview of Oracle Database: Understanding Oracle’s relational database model, Introduction to Oracle SQL Developer and SQL*Plus, Connecting to an Oracle database.
• SQL Basics: Introduction to Structured Query Language (SQL), Writing simple SELECT queries, Filtering data with the WHERE clause, Sorting results using ORDER BY.

Advanced SELECT Queries

• Working with Multiple Columns: Selecting specific columns, Using column aliases, Concatenating fields, and formatting output.
• Filtering Data: Using comparison operators, Logical operators (AND, OR, NOT), Pattern matching with LIKE, Handling NULL values in Oracle.
• Sorting and Limiting Results: Sorting query results using ORDER BY, Using ROWNUM and FETCH FIRST to limit rows returned.

Joins and Subqueries

• Introduction to Joins: Understanding Inner Joins, Outer Joins (Left, Right, Full), and Cross Joins in Oracle.
• Advanced Joins: Using multiple joins in a query, Self-joins, and hierarchical queries with CONNECT BY and PRIOR.
• Subqueries: Writing subqueries in the WHERE, SELECT, and FROM clauses, Correlated subqueries, and EXISTS/NOT EXISTS conditions.

Aggregate Functions and Grouping Data

• Aggregate Functions: Utilizing COUNT, SUM, AVG, MIN, MAX functions for data summarization in Oracle.
• Grouping Data: Grouping query results with GROUP BY, Filtering grouped data using HAVING, Using GROUPING SETS and ROLLUP for advanced aggregation.
• Cube Operations: Understanding CUBE operations for multidimensional analysis.

Data Manipulation

• Inserting Data: Writing INSERT INTO statements, Inserting data from another table using INSERT INTO SELECT, Bulk inserts.
• Updating Data: Writing UPDATE statements, Updating multiple rows, Using the MERGE statement for conditional updates.
• Deleting Data: Writing DELETE statements with conditions, Truncating tables, and using DELETE with RETURNING clause.

Advanced Querying Techniques

• Using Case Statements: Implementing conditional logic in SELECT with CASE, Complex conditions and nested CASE statements.
• String Functions: Working with string functions (CONCAT, SUBSTR, LENGTH, INSTR, REPLACE) in Oracle.
• Date and Time Functions: Manipulating date and time data, Using TO_DATE, TO_CHAR, and date arithmetic, Working with INTERVAL and TIMESTAMP.

Indexing and Query Optimization

• Introduction to Indexes: Understanding Oracle indexes (B-tree, Bitmap, Function-based indexes), Creating and dropping indexes, Using indexes for query optimization.
• Query Optimization Techniques: Analyzing query execution plans with EXPLAIN PLAN, Using HINTS for query optimization, Best practices for writing efficient Oracle SQL queries.
• Partitioning: Introduction to table partitioning in Oracle, Benefits of partitioning for query performance.

Practical Exercises and Final Project

• Hands-On Practice: Writing complex Oracle SQL queries, Analyzing query performance, and applying optimizations.
• Final Project: Designing and executing a set of advanced queries on an Oracle database, Presenting findings and optimizations in a structured report.