mongodb find values that contain whitespace-CodePudding

i have the following sample documents:

{_id: "1", value: " 1"}
{_id: "2", value: "2"}
{_id: "3", value: "3 "}

How can i run a mongdb find function that returns the documented with a value that contains a space? So in this case, it would return 1 because it has a space at the beginning, and 3 because it has a space at the end

CodePudding user response：

Use $regex operator with regex pattern:

(^\s. )|(. \s$)

(^\s.*) - Group (()) with starts with (^) whitespace (\s) match any character (.) with at least one occurrence.

| - Or.

(.*\s$) - Group (()) with match any character (.) with at least one occurrence ( ) at the end ($).

Sample Regex 101 and Test Data

db.collection.find({
  value: {
    $regex: "(^\\s. )|(. \\s$)"
  }
})

Sample Mongo Playground