/******************************************************************************************
Getting Messy with SQL Reporting: Preventive Breast Imaging
RCHC Analytics Academy: 5/12/2022
Created by: Nicholas Alonzo (nicholas@diversifyds.org)
Description:
  Hands-on code-along script to work with preventive breast imaging demo tables
*******************************************************************************************/

-- STEP 1: Define the base population





-- STEP 2: JOIN external breast imaging data with base population





-- STEP 3: Match notes patterns with regular expressions and extract with SUBSTRING()

/******************************************************************************************
| SUBSTRING(): Returns a matched pattern OR a captured group in matched pattern           |
|-----------------------------------------------------------------------------------------|
| Characters 	| Description                                                              	|
|-------------|---------------------------------------------------------------------------|
| .          	| any single character                                                     	|
| \d         	| Match a digit (0-9)                                                      	|
| \w         	| Match an alphanumeric (a-z, 0-9) character including _                   	|
| \s         	| Match a space character                                                  	|
| \y         	| Match the beginning or end of a sequence of words or numbers              |
| |          	| Match the pattern on the left OR right                                   	|
| ( )        	| Group items into one logical unit or capture pattern to extract          	|
| *          	| 0 or more matches of the previous item                                    |
| +          	| 1 or more matches of the previous item                                   	|
| ?          	| 0 or 1 matches of the previous item                                      	|
| {m}        	| Exactly m (number) matches of the previous item                          	|
| {m, }      	| Exactly m (number) matches or more of the previous item                  	|
| {m, n}     	| Exactly m (number) matches up to n (number) matches of the previous item 	|
| ^          	| Match at the beginning, used at the beginning of the pattern             	|
| $          	| Match at the end, used at the end of a pattern                           	|
******************************************************************************************/

-- testing regular expressions with SUBSTRING() recap
SELECT SUBSTRING('This is a date 4/12/2022', '');

SELECT SUBSTRING('This is another date 4/12/22', '');


-- STEP 4: Combine internal and external breast imaging data





-- STEP 5: Final select statement





-- STEP 6: What else is left to do?