Add Batch Insert Records With createMany as a Prisma TIL

Author: jbranchaud

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).
 
-_1305 TILs and counting..._
+_1306 TILs and counting..._
 
 ---
 
@@ -742,6 +742,7 @@ _1305 TILs and counting..._
 ### Prisma
 
 - [Apply Separate Formatting With A Blank Line](prisma/apply-separate-formatting-with-a-blank-line.md)
+- [Batch Insert Records With createMany](prisma/batch-insert-records-with-create-many.md)
 - [Execute A Raw SQL Query](prisma/execute-a-raw-sql-query.md)
 - [Grab A Limited Set Of Records](prisma/grab-a-limited-set-of-records.md)
 - [Specify Alternate Location For Prisma Schema](prisma/specify-alternate-location-for-prisma-schema.md)

prisma/batch-insert-records-with-create-many.md

@@ -0,0 +1,41 @@
+# Batch Insert Records With createMany
+
+As part of its suite of CRUD functionality, [Prisma has a `createMany`
+function](https://www.prisma.io/docs/reference/api-reference/prisma-client-reference#createmany)
+that allows you to `insert` many records at once with your target database.
+This will perform one large insert statement which will generally be faster
+than an equivalent series of individual insert statements.
+
+```javascript
+const createResult = await prisma.books.createMany({
+  data: [
+    { isbn: '123', title: 'The Goldfinch' },
+    { isbn: '345', title: 'Piranesi' },
+    { isbn: '987', title: 'The Fifth Season' },
+  ],
+  skipDuplicates: true
+})
+```
+
+With the `skipDuplicates` option, any inserts that would result in a duplicate
+record (`isbn` is my unique key in this example) will be skipped.
+
+The result of the query will include a `count` key to let you know how many
+records were actually inserted.
+
+If I'm bulk inserting a _ton_ of data, I like to chunk it up so that I'm not
+creating queries that are too big. For a recent script, I found that `1000` was
+a good chunking number.
+
+```javascript
+import 'chunk' from 'lodash/chunk'
+
+const chunkedBatchInsert = async (records) => {
+  for(const batch of chunk(records, 1000)) {
+    await prisma.books.createMany({
+      data: batch,
+      skipDuplicates: true
+    })
+  }
+}
+```