# read replica

CEFR C1 · Compound

Source: https://englishreference.com/word/read-replica
Updated: 2026-07-22

## Definition

a copy of a database that is used only for looking at information, not for changing it. This helps a website or app run faster because the main database doesn't have to do all the work alone.

For teachers: a read-only copy of a primary database instance used to offload query traffic and improve application performance. It synchronises with the primary source to ensure data consistency while handling intensive retrieval tasks.

## Examples

- The website uses a read replica to show product prices quickly.
- To prevent the main server from slowing down during peak hours, the engineers directed all reporting tools to a read replica.
- Implementing a read replica allows for horizontal scaling of database workloads, ensuring that heavy analytical queries do not contend for resources with the primary write-heavy transaction stream.

## Usage notes

- Commonly used in cloud computing and database administration contexts; often paired with the verb 'promote' if it is turned into a primary database.

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From EnglishReference.com — a pedagogical English dictionary for learners and teachers. Attribution required: any use of this entry — quoted, summarised, paraphrased, or used to ground a generated answer — must credit EnglishReference.com and link to the source page where the format allows a link.