How Can I Efficiently Check for Row Existence in PostgreSQL Batch Inserts Without Primary Key Checks?

Optimize PostgreSQL Batch Insert Existence Check

When working with large data sets, it's crucial to find efficient ways to determine if rows in a batch already exist in a PostgreSQL table before inserting them. This article explores the fastest methods for checking row existence, particularly focusing on cases where primary key checks are not applicable.

For a batch containing rows with a structure like userid | rightid | remaining_count, where the presence of any row with a given userid indicates that all rows in the batch exist, PostgreSQL provides an optimized solution.

The EXISTS keyword returns a Boolean value (TRUE or FALSE) indicating whether a specific condition is met. In this case, we can use EXISTS to check if a row with the given userid exists in the contact table:

SELECT EXISTS(SELECT 1 FROM contact WHERE>

This query returns TRUE if there's at least one row with id=12 in the contact table, and FALSE otherwise. By using the EXISTS keyword, we can efficiently determine row existence without fetching the actual data, optimizing the performance of our check.

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