Batch limits and best practices in Firebase - Step-by-Step Execution

Process Flow - Batch limits and best practices

Start Batch Operation

↓

Add Write Operations

↓

Check Batch Size <= 500?

No→Error: Batch limit exceeded

Yes↓

Commit Batch

↓

Batch Writes Applied

↓

End

This flow shows how a batch write operation is prepared, checked against the 500 write limit, committed if valid, or errors if the limit is exceeded.

Execution Sample

Firebase

batch = firestore.batch()
batch.set(docRef1, data1)
batch.update(docRef2, data2)
// ... up to 500 writes
batch.commit()

This code creates a batch, adds write operations, and commits them if the batch size is within limits.

Process Table

Step	Action	Batch Size	Check Limit (<=500)	Result
1	Initialize batch	0	N/A	Batch created
2	Add set operation	1	1 <= 500: Yes	Operation added
3	Add update operation	2	2 <= 500: Yes	Operation added
4	Add delete operation	3	3 <= 500: Yes	Operation added
...	...	...	...	...
500	Add 500th operation	500	500 <= 500: Yes	Operation added
501	Add 501st operation	501	501 <= 500: No	Error: Batch limit exceeded
Commit	Commit batch	<=500	Commit allowed only if <=500	Batch writes applied or error

💡 Batch commit only succeeds if batch size is 500 or less; exceeding 500 causes error.

Status Tracker

Variable	Start	After 1	After 2	After 3	...	After 500	After 501
batch_size	0	1	2	3	...	500	501

Key Moments - 3 Insights

Why can't we add more than 500 operations in one batch?

Firebase limits batch writes to 500 operations to ensure performance and reliability, as shown in execution_table row 7 where adding the 501st operation causes an error.

What happens if we try to commit a batch with more than 500 writes?

The commit will fail with an error because the batch size exceeds the limit, as indicated in the exit_note and execution_table row 7.

Can we split a large number of writes into multiple batches?

Yes, to handle more than 500 writes, split them into multiple batches each with 500 or fewer operations, then commit each batch separately.

Visual Quiz - 3 Questions

Look at the execution_table, what is the batch size after adding the third operation?

A 3

B 2

C 1

D 0

💡 Hint

Check the 'Batch Size' column at Step 4 in the execution_table.

At which step does the batch size exceed the allowed limit?

A Step 500

B Commit step

C Step 501

D Step 499

💡 Hint

Look for the first 'No' in the 'Check Limit' column in the execution_table.

If you want to write 1200 documents, how should you organize your batches?

A One batch with 1200 writes

B Three batches with 500, 500, and 200 writes

C Three batches with 400 writes each

D Two batches with 600 writes each

💡 Hint

Recall the batch limit is 500 writes per batch from the concept_flow and execution_table.

Concept Snapshot

Firebase batch writes allow up to 500 operations per batch.
Add operations to batch, check size <= 500 before commit.
Commit applies all writes atomically.
Exceeding 500 causes error.
Split large writes into multiple batches.

Full Transcript

This visual execution shows how Firebase batch writes work with a limit of 500 operations per batch. We start by creating a batch, then add write operations one by one. Each addition increases the batch size. Before committing, the batch size is checked to ensure it does not exceed 500. If it does, an error occurs and the commit fails. To handle more than 500 writes, split them into multiple batches and commit each separately. This ensures reliable and efficient writes to Firestore.