SQL - Basics Flashcards
The very basics of SQL.
What does SQL stand for?
Structured Query Language.
What is SQL used for?
To communicate with databases.
Which statement is used to select a column?
SELECT.
Which statement is used to choose the table?
FROM.
Which statement is used to filter data?
WHERE.
What is the basic order of an SQL query?
SELECT, FROM, WHERE.
How do you select the ‘first_name’ column from a table called ‘customer_name’?
SELECT first_name
FROM customer_name;
How do you select multiple columns?
Separate column names with commas.
How do you select ‘customer_id’ and ‘first_name’ from ‘customer_name’?
SELECT customer_id, first_name
FROM customer_name;
How do you filter results by a condition?
Use WHERE.
How do you select customers with first_name ‘Tony’?
SELECT first_name
FROM customer_name
WHERE first_name = ‘Tony’;
How do you add more than one condition in a query?
Use AND or OR.
How do you filter results where a value is greater than a number?
Use > in the WHERE clause.
How do you write a comment in SQL?
Use -- for single-line comments.
Are SQL keywords case-sensitive?
No, they are not case-sensitive.
