sql-select

Question 1

What is SQL and how is it different from languages like JavaScript?

Answer 1

SQL is a domain-specific language used in programming and designed for managing data held in a relational database management system (RDBMS), or for stream processing in a relational data stream management system (RDSMS).
SQL is a declarative programming language (programmers describe the results they want and the programming environment comes up with its own plan for getting those results) and JavaScript is an imperative programming languages ( you basically tell the JavaScript runtime what to do and how to do it)

Question 2

How do you retrieve specific columns from a database table?

Answer 2

select statement “keyword”,

Question 3

How do you filter rows based on some specific criteria?

Answer 3

where clause operator “table”= ‘text value’
where “product”.”category” = ‘cleaning’
(after the from clause)

Question 4

What are the benefits of formatting your SQL?

Answer 4

consistent style and therefore readability.

Question 5

What are four comparison operators that can be used in a where clause?

Answer 5

=, and !=

Question 6

How do you limit the number of rows returned in a result set?

Answer 6

limit clause

comes last. includes a literal integer number w/ no quotes

Question 7

How do you retrieve all columns from a database table?

Answer 7

replacing the list of column names with an * asterisk.

Question 8

How do you control the sort order of a result set?

Answer 8

with keyword desc

order by “price” desc