Add Get Idea Of What Is In A JSON Column as a MySQL TIL

README.md

@@ -10,7 +10,7 @@ pairing with smart people at Hashrocket.
 
 For a steady stream of TILs, [sign up for my newsletter](https://crafty-builder-6996.ck.page/e169c61186).
 
-_1695 TILs and counting..._
+_1697 TILs and counting..._
 
 See some of the other learning resources I work on:
 
@@ -380,6 +380,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Last Commit A File Appeared In](git/last-commit-a-file-appeared-in.md)
 - [List All Files Added During Span Of Time](git/list-all-files-added-during-span-of-time.md)
 - [List All Files Changed Between Two Branches](git/list-all-files-changed-between-two-branches.md)
+- [List All Git Aliases From gitconfig](git/list-all-git-aliases-from-gitconfig.md)
 - [List Branches That Contain A Commit](git/list-branches-that-contain-a-commit.md)
 - [List Commits On A Branch](git/list-commits-on-a-branch.md)
 - [List Different Commits Between Two Branches](git/list-different-commits-between-two-branches.md)
@@ -762,6 +763,7 @@ If you've learned something here, support my efforts writing daily TILs by
 - [Doing Date Math](mysql/doing-date-math.md)
 - [Dump A Database To A File](mysql/dump-a-database-to-a-file.md)
 - [Echo A Message From A SQL File](mysql/echo-a-message-from-a-sql-file.md)
+- [Get Idea Of What Is In A JSON Column](mysql/get-idea-of-what-is-in-a-json-column.md)
 - [Ignore Duplicates When Inserting Records](mysql/ignore-duplicates-when-inserting-records.md)
 - [List Databases And Tables](mysql/list-databases-and-tables.md)
 - [Run Statements In A Transaction](mysql/run-statements-in-a-transaction.md)

git/list-all-git-aliases-from-gitconfig.md

@@ -0,0 +1,28 @@
+# List All Git Aliases From gitconfig
+
+Running the `git config --list` command will show all of the configuration
+settings you have for `git` relative to your current location. Though most of
+these setting probably live in `~/.gitconfig`, you may also have some locally
+specified ones in `.git/config`. This will grab them all including any `alias`
+entries.
+
+We can narrow things down to just `alias` entries using the `--get-regexp` flag.
+
+```bash
+$ git config --get-regexp '^alias\.'
+
+alias.ap add --patch
+alias.authors shortlog -s -n -e
+alias.co checkout
+alias.st status
+alias.put push origin HEAD
+alias.fixup commit --fixup
+alias.squash commit --squash
+alias.doff reset HEAD^
+alias.add-untracked !git status --porcelain | awk '/\?\?/{ print $2 }' | xargs git add
+alias.reset-authors commit --amend --reset-author -CHEAD
+```
+
+I use `git doff` all the time on feature branches to "pop" the latest commmit
+onto the working copy. I was trying to remember exactly what the `git doff`
+command is and this was an easy way to check.

mysql/get-idea-of-what-is-in-a-json-column.md

@@ -0,0 +1,40 @@
+# Get Idea Of What Is In A JSON Column
+
+While digging through some data trying to reacquaint myself with the overall
+schema and data model, I ran into an issue selecting rows from this
+`content_resource` table. There was so much text packed in to the `"body"`,
+`"summary"`, and `"description"` key-value pairs of `fields` JSON column that a
+simple `select * ... limit 3;` was overwhelming the screen with text and table
+formatting characters (i.e. `+------+-------`).
+
+I figured the `fields` JSON followed a reliable structure, at least for records
+of the same `type`. So, let's start by only grabbing the
+[`json_keys`](https://dev.mysql.com/doc/refman/8.4/en/json-search-functions.html#function_json-keys)
+so that I can get a sense of the shape of the JSON.
+
+```sql
+select id, json_keys(fields)
+from content_resource
+where type = 'post'
+limit 3;
+
++-----+-----------------------------------------------------------------------------------------------------------+
+| id  | json_keys(`fields`)                                                                                       |
++-----+-----------------------------------------------------------------------------------------------------------+
+|  1  | ["body", "slug", "state", "title", "summary", "postType", "visibility", "description", "originalLessonId"] |
+|  2  | ["body", "slug", "state", "title", "summary", "postType", "visibility", "description", "originalLessonId"] |
+|  3  | ["body", "slug", "state", "title", "summary", "postType", "visibility", "description", "originalLessonId"] |
++-----+-----------------------------------------------------------------------------------------------------------+
+```
+
+For the `post` type, I see the same keys for this sampling of rows. Now I have
+an idea what keys are present and can start digging in further.
+
+My next query might look something like this:
+
+```sql
+select id, fields->'$.slug', fields->'$.title', fields->'$.state'
+from content_resource
+where type = 'post'
+limit 3;
+```