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- Aggregation Framework Operators >
- String Aggregation Operators
String Aggregation Operators¶
| Name | Description |
|---|---|
$concat |
Concatenates two strings. |
$strcasecmp |
Compares two strings and returns an integer that reflects the comparison. |
$substr |
Takes a string and returns portion of that string. |
$toLower |
Converts a string to lowercase. |
$toUpper |
Converts a string to uppercase. |