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Document read replication and transaction behaviour #574

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Document read replication and transaction behaviour #574

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Document read replication and transaction behaviour
Rochet2 Sep 6, 2023
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Merge branch 'main' into patch-1
ephys Apr 11, 2024
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2 changes: 1 addition & 1 deletion docs/other-topics/read-replication.md
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Expand Up @@ -36,4 +36,4 @@ Sequelize uses a pool to manage connections to your replicas. Internally Sequeli

If you want to modify these, you can pass pool as an options when instantiating Sequelize, as shown above.

Each `write` or `useMaster: true` query will use write pool. For `SELECT` read pool will be used. Read replica are switched using a basic round robin scheduling.
Each `write` or `useMaster: true` query will use write pool. For `SELECT` read pool will be used. When all reads and writes when using transactions will be sent to the write pool by default. Read replica are switched using a basic round robin scheduling.
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Copilot AI Apr 5, 2026

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This new sentence is grammatically incorrect and ambiguous: "When all reads and writes when using transactions will be sent…". Consider rewriting as separate, clear sentences (e.g., "Within a transaction, all queries use the same connection. With replication enabled, transactions default to acquiring from the write pool, so SELECTs in that transaction also use the write pool."). This more directly explains why SELECT behaves differently in a transaction.

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Each `write` or `useMaster: true` query will use write pool. For `SELECT` read pool will be used. When all reads and writes when using transactions will be sent to the write pool by default. Read replica are switched using a basic round robin scheduling.
Each `write` or `useMaster: true` query will use the write pool. `SELECT` queries will use the read pool by default. Within a transaction, all queries use the same connection, so with replication enabled they are sent to the write pool by default. Read replicas are switched using a basic round robin scheduling.

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Copilot AI Apr 5, 2026

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Correct grammar: "Read replica are" should be "Read replicas are".

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Each `write` or `useMaster: true` query will use write pool. For `SELECT` read pool will be used. When all reads and writes when using transactions will be sent to the write pool by default. Read replica are switched using a basic round robin scheduling.
Each `write` or `useMaster: true` query will use write pool. For `SELECT` read pool will be used. When all reads and writes when using transactions will be sent to the write pool by default. Read replicas are switched using a basic round robin scheduling.

Copilot uses AI. Check for mistakes.