SQL Queries and their Uses

[sahithya]

SELECT: Retrieving Data
The SELECT query is the heart of SQL, allowing you to fetch data from one or more tables. Understand its syntax, using aliases, and apply aggregate functions like COUNT, SUM, and AVG .

WHERE: Filtering Data
The WHERE clause enables you to filter rows based on specific conditions, refining query results to meet precise criteria. Learn to use logical operators, comparison operators, and wildcards for efficient data filtering.

GROUP BY: Aggregating Data
GROUP BY, paired with aggregate functions, allows you to group rows based on specific columns and calculate summary information such as totals, averages, and counts.

ORDER BY: Sorting Results
ORDER BY lets you sort query results in ascending or descending order based on one or more columns. Perfect your sorting skills to present data in a meaningful way.

LIMIT: Controlling Output
LIMIT is a valuable query for restricting the number of rows returned in the result set, particularly helpful when dealing with large datasets.

DISTINCT: Eliminating Duplicates
DISTINCT eliminates duplicate rows from the result set, ensuring unique records are displayed.

INSERT: Adding Data
The INSERT query inserts new records into a table. Master this query to add data efficiently to your database.

UPDATE: Modifying Data
UPDATE is used to modify existing records in a table. Understanding this query ensures accurate data updates.

DELETE: Removing Data
DELETE allows you to remove specific rows from a table. Caution is necessary while using this query to prevent data loss.

JOIN: Combining Data from Multiple Tables
JOIN operations are vital for combining data from different tables. Master INNER JOIN, LEFT JOIN, RIGHT JOIN, and FULL JOIN to handle complex data retrieval and analysis tasks.