Skip to content

$strcasecmp

The $strcasecmp operator performs a case-insensitive comparison of two strings and returns:

  • 0 if they are equal (ignoring case)
  • 1 if the first is greater
  • -1 if the second is greater

📌 Syntax

{ "$strcasecmp": [ <string1>, <string2> ] }

✅ Base Example 1 – Equal Strings

📥 Input Document

{ "input1": "hello", "input2": "HELLO" }

📌 Expression

{ "$strcasecmp": ["$input1", "$input2"] }

📤 Output

0

✅ Base Example 2 – Alphabetical Check

📥 Input Document

{ "input1": "apple", "input2": "banana" }

📌 Expression

{ "$strcasecmp": ["$input1", "$input2"] }

📤 Output

-1

🧱 Ecommerce Example – Compare Category Codes for Sorting

📌 Pipeline

[
  { "$unwind": "$items" },
  {
    "$project": {
      "isCategoryMatch": {
        "$eq": [
          { "$strcasecmp": ["$items.category", "FASHION"] },
          0
        ]
      },
      "name": "$items.name"
    }
  }
]

📥 Input Document

{
  "items": [
    { "name": "Jacket", "category": "Fashion" },
    { "name": "Speaker", "category": "Electronics" }
  ]
}

📤 Output

[
  { "isCategoryMatch": true, "name": "Jacket" },
  { "isCategoryMatch": false, "name": "Speaker" }
]

🔧 Common Use Cases

  • Case-insensitive comparisons
  • Field normalization for filtering
  • Use in $project, $match, or conditional logic
  • $eq, $toLower, $cmp, $cond

🧠 Notes

  • Both arguments must be strings.
  • Returns numeric value based on case-insensitive lexicographical comparison.