Regex Substring Queries in MongoDB-Go-Driver
Regex substring queries are essential for performing complex text searches in MongoDB. While the mongo shell offers straightforward ways to query using regex patterns, it can be challenging to replicate this functionality using the official Go mongo driver.
Issue Overview
A developer encountered difficulties in retrieving entries using a regex substring query with the mongo-go-driver. Despite following the documented examples, the code failed to return any results.
Cause
Upon further investigation, the issue stemmed from an incorrect format for the Pattern field of the primitive.Regex struct. In the original code, the Pattern contained forward slashes (/), which are not necessary for usage in the Go mongo driver.
Solution
To resolve the issue, the Pattern field in primitive.Regex should only include the regex pattern itself, without any slashes. For example:
<code class="go">filter := bson.D{{"text", primitive.Regex{Pattern: "he", Options: ""}}}</code>
This change allows the Go mongo driver to correctly interpret the regex pattern and perform the substring query successfully.
Expected Results
With the corrected code, the query should return two documents from the collection:
{ "_id" : ObjectId("5c9cc7e9950198ceeefecbdd"), "text" : "hello world" }, { "_id" : ObjectId("5c9cc7f6950198ceeefecbec"), "text" : "hello" }
These documents contain the "he" substring in their "text" field, matching the regex pattern specified in the query.
The above is the detailed content of How to Perform Regex Substring Queries in MongoDB with the Go Driver?. For more information, please follow other related articles on the PHP Chinese website!

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