Intro
What is a Database Manipulation Langauge?
Select
SELECT
SELECT * FROM People
This is used to retrieve data from a database table(or multiple tables)
You can retrieve all columns from the tables, or restrict to specific rows
WHERE
This is used to filter results based on the criteria given
ORDER BY
This is used to sort the table by a certain column
GROUP BY
This is used to collate with certain shared values together
Aggregates
Aggregate Funtions (Sum, Count, average)
These queries are all used with the SELECT Query and all return number as the response to the query.
SUM
This sums up values within a certain column.
COUNT
The returns the number of rows retrieved by a statement
AVG
This returns the mean average of the attributes specified
Inner Join
INNER JOIN
This combines data from two tables (or more) into a single query.
Insert
INSERT
This adds a new row into a database table.
Update
UPDATE
The update alters the data stored within a row or rows, depending on the parameters given.
Delete
DELETE
This query removes a row or rows, depending on the query. If you don’t specify what data to delete then it will delete all data in a table