4.5 Databases (SQL)

Question 1

Select Data

Retrieving specifc columns from a table

Answer 1

SELECT column1, column2
FROM table_name;

Question 2

Select With Condition

Retrives all columns from a table where the specified column is true

Answer 2

SELECT *
FROM table_name
WHERE condition;

Question 3

Create Table

Creates a new table with specified columns and data types

Answer 3

CREATE TABLE table_name (
column1 datatype,
column2 datatype
);

Question 4

Insert Data

Adds new rows od data into a table

Answer 4

INSERT INTO table_name (column1, column2)
VALUES (value1, values2);

Question 5

Update Data

Modifies existing data in a table

Answer 5

    UPDATE table_name
       SET column1 = value1
   WHERE condition;

Question 6

Select With Condition on Numeric Values

Retrieves specific columns from a table where a numeric condition is met

Answer 6

SELECT column1, column2
FROM table_name
WHERE numeric_column < value;

Question 7

Select With Multiple Conditions

Retrieves specific columns from table where multiple conditions are met

Answer 7

SELECT column1, column2
FROM table_name
WHERE condition1 AND condition2

Question 8

Select with OR Condition

Retrieves specific columns from table where at least 1 condition is met

Answer 8

SELECT column1, column2
FROM table_name
WHERE condition1 OR condition2

Question 9

Subquery

Uses a nested query to retrive data based on result of another query.

Answer 9

SELECT column1, column2
FROM table_name
WHERE column = (
  SELECT column
  FROM table_name
  WHERE condition
);