From 5bcd67946c16fe820a5bc9c6a06efa972fb53aeb Mon Sep 17 00:00:00 2001
From: jbranchaud <jbranchaud@gmail.com>
Date: Mon, 27 Nov 2023 17:46:42 -0600
Subject: [PATCH] Add Filter Out Results Based On List Of Values as a jq TIL

---
 README.md                                     |  3 +-
 ...ter-out-results-based-on-list-of-values.md | 34 +++++++++++++++++++
 2 files changed, 36 insertions(+), 1 deletion(-)
 create mode 100644 jq/filter-out-results-based-on-list-of-values.md

diff --git a/README.md b/README.md
index d97f327..a9c2efa 100644
--- a/README.md
+++ b/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).
 
-_1349 TILs and counting..._
+_1350 TILs and counting..._
 
 ---
 
@@ -499,6 +499,7 @@ _1349 TILs and counting..._
 - [Count Each Collection In A JSON Object](jq/count-each-collection-in-a-json-object.md)
 - [Count The Number Of Things In A JSON File](jq/count-the-number-of-things-in-a-json-file.md)
 - [Extract A List Of Values](jq/extract-a-list-of-values.md)
+- [Filter Out Results Based On List Of Values](jq/filter-out-results-based-on-list-of-values.md)
 - [Find All Objects In An Array Where Key Is Set](jq/find-all-objects-in-an-array-where-key-is-set.md)
 - [Find All Objects With A Matching Key Value Pair](jq/find-all-objects-with-a-matching-key-value-pair.md)
 - [Get The First Item For Every Top-Level Key](jq/get-the-first-item-for-every-top-level-key.md)
diff --git a/jq/filter-out-results-based-on-list-of-values.md b/jq/filter-out-results-based-on-list-of-values.md
new file mode 100644
index 0000000..95d3421
--- /dev/null
+++ b/jq/filter-out-results-based-on-list-of-values.md
@@ -0,0 +1,34 @@
+# Filter Out Results Based On List Of Values
+
+Let's say we have an array of objects in a JSON file. We want to extract some
+data about each of those objects, but first we want to filter out some of the
+objects that we don't need. This will be based on a list of IDs.
+
+The JSON might look something like this:
+
+```json
+[
+  {'id': '123', ...},
+  {'id': '456', ...},
+  {'id': '789', ...},
+  {'id': '963', ...},
+  ...
+]
+```
+
+With the [`select`](https://jqlang.github.io/jq/manual/#select) function, we
+can filter the array down to those objects whose IDs are
+[`not`](https://jqlang.github.io/jq/manual/#and-or-not)
+[`inside`](https://jqlang.github.io/jq/manual/#inside) the list of IDs to
+exclude.
+
+```
+jq '.[] | select([.id] | inside["456", "963"] | not)' data.json
+```
+
+Inside that `select`, we grab the `id` as a single value array, check if that
+value is inside our _exclude_ array, and then invert that result. If there is a
+match, that object will be filtered out.
+
+We can then chain additional filtering and extraction on to the end of the
+query to produce the result we want.