ES7 multiple async/await functions in parallel execution.

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ES7 multiple async/await functions in parallel execution.

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Last edited Aug 17, 2016

Created on Sep 27, 2018

This example demonstrates how to refactor a sequential async/await loop into parallel execution using JavaScript Promises. It shows three versions of the same Express route handler that fetch product reviews and then look up user details for each review. The code uses async/await syntax, `Promise.all`, and `Array.prototype.map` to concurrently query an `accountsQuery` data source for each review, returning a merged JSON response. The final solution attaches a `.catch` handler to each review promise, ensuring a single failed lookup does not reject the entire `Promise.all` batch.

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