4. Data Analytics - Data, Data, Everywhere - Week 4

Definitions:

Columns // ordered by letters

Rows // ordered by numbers

Attribute // a characteristic or quality of data used to label a column in a table

    - Referred to as column names, column labels, headers, or header rows

Observation // all of the attributes for something contained in a row of a data table

Formula // a set of instructions that performs a specific action using a data in a spreadsheet

Query // a request for data or information from a database

Syntax // a predetermined structure of a language


SQL Uses:

    - Store

    - Organize

    - Analyze


SQL Databases:

    - MySQL

    - Oracle

    - PostgreSQL

    - Microsoft SQL Server


SQL have queries which are universal.


"Can have multiple conditions"


The syntax of every SQL query is the same: 

    - Use SELECT to choose the columns you want to return.

    - Use FROM to choose the tables where the columns you want are located.

    - Use WHERE to filter for certain information.


SQL Syntax:

    - Comments 

            /* This is a block comment */

            -- This is a line comment

    - SELECT *

        - Selects all columns

    - WHERE field1 LIKE 'TEST%'

        - This filters anything that has a likeness that includes "TEST"

        - Sometimes * is used instead of %

    - Aliases for variables use AS

    - Does not equal, use this sign <>

        EX: field1 <> 'INT'

    - AND

        - Can use AND instead of commas to separate multiple conditions.



Additional Resources:

https://support.microsoft.com/en-us/office/excel-video-training-9bc05390-e94c-46af-a5b3-d7c22f6990bb

https://support.google.com/a/users/answer/9300022

https://support.google.com/a/users/answer/9282959?visit_id=637361702049227170-1815413770&rd=1

https://towardsdatascience.com/sql-cheat-sheet-776f8e3189fa?gi=8a64767b9d2b

https://www.w3schools.com/sql/default.asp


https://public.tableau.com/en-us/s/resources

https://www.rstudio.com/

https://www.rstudio.com/resources/cheatsheets/

https://rstudio.cloud/learn/primers/3

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