Postgres

Question 1

What is PostgreSQL and what are some alternative relational databases?

Answer 1

MongoDB (NoSQL), MySQL, Microsoft SQL Server, Oracle, IBM

Question 2

What are some advantages of learning a relational databases?

Answer 2

Structures, relationships, data integrity, simple, normalization

Question 3

What is one way to see if PostgreSQL is running?

Answer 3

top, status

Question 4

What is a database schema?

Answer 4

How data should be organized

Question 5

What is a table?

Answer 5

Relations

Question 6

What is a row?

Answer 6

data

Question 7

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

Answer 7

Structured Query Language, declarative language, describing the results they want

Question 8

How do you retrieve specific columns from a database table?

Answer 8

select column

Question 9

How do you filter rows based on some specific criteria?

Answer 9

where

Question 10

What are the benefits of formatting your SQL?

Answer 10

Readability

Question 11

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

Answer 11

less than
greater than
equal
not equal

Question 12

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

Answer 12

limit

Question 13

How do you retrieve all columns from a database table?

Answer 13

*

Question 14

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

Answer 14

order by … asc/desc

Question 15

How do you add a row to SQL table?

Answer 15

INSERT INTO

Question 16

What is a tuple?

Answer 16

List of values

Question 17

How do you add multiple rows to a SQL table at once?

Answer 17

, delimit values

Question 18

How do you get back the row being inserted into a table without a separate select statement?

Answer 18

returning *

Question 19

How do you update rows in a database table?

Answer 19

UPDATE

SET

Question 20

Why is it important to include a where clause in your update statemetns?

Answer 20

You will update everything

Question 21

How do you delete rows from a database table?

Answer 21

DELETE FROM

Question 22

How do you accidently delete all rows from a table?

Answer 22

DELETE FROM TABLE

Question 23

What is a foreign key?

Answer 23

Refer to another row of data from another table

Question 24

How do you join two SQL tables?

Answer 24

join using

Question 25

How do you temporarily rename columns or tables in a SQL statement?

Answer 25

alias using AS

Question 26

What are some examples of aggregate functions?

Answer 26

min, sum, avg, count

Question 27

What is the purpose of a group by clause?

Answer 27

To group by a similar value

Question 28

What are the three states a promise can be in?

Answer 28

fulfilled, pending, rejected

Question 29

How do you handle the fulfillment of a promise?

Answer 29

then()

Question 30

How do you handle the rejection of a promise?

Answer 30

catch