For an instructor lead, in-depth look at learning SQL click below.
If you’re interested in delving into the realm of database management and manipulation, then SQL is a language you must usher yourself into. SQL (Structured Query Language) is essentially used to communicate with and manipulate databases. It is widely utilized for its simplicity, power and widespread acceptance. In this blog post, we will guide you on how to start your journey with SQL, discussing some of the essential SQL commands with examples.
Understanding the SQL SELECT Statement
The SELECT statement is used to select data from a database. The data returned is stored in a result table, called the result-set.
|
1 2 3 |
SELECT column1, column2 FROM table_name; |
In this example, “column1” and “column2” are the names of the columns you wish to select from “table_name”. If you want to select all columns, you would instead use *.
|
1 2 3 |
SELECT * FROM table_name; |
The SQL WHERE Clause
While the SELECT statement is great for retrieving all the data from a specific set of columns, there might be a time when you want to retrieve a subset of data, depending on certain conditions. This is where the WHERE clause comes in.
|
1 2 3 |
SELECT column1, column2 FROM table_name WHERE condition; |
The SQL INSERT INTO Statement
Used to insert new data into a database, the INSERT INTO statement adds new rows of data to existing tables. The SQL INSERT INTO syntax has two primary forms: The first form does not specify the column names where the data will be inserted, only their values:
|
1 2 3 |
INSERT INTO table_name VALUES (value1, value2, value3, ...); |
The SQL UPDATE Statement
This is used to modify the existing records in a table. The basic syntax looks like this:
|
1 2 3 4 5 |
UPDATE table_name SET column1 = value1, column2 = value2, ... WHERE condition; |
SQL DELETE Statement
Finally, the DELETE statement is used to delete existing records in a table.
|
1 2 3 |
DELETE FROM table_name WHERE condition; |
Conclusion
And that’s it! These are the foundational SQL commands required to start your journey into database management and analytics. In the next posts, we’ll delve into more advanced topics like Joins, Unions, and Stored Procedure. For now, happy querying!