In MariaDB, CHR() is a built-in string function that returns a character based on the code values provided as an argument.
Tag: what is
How ORD() Works in MariaDB
In MariaDB, ORD() is a built-in string function that returns the numeric character code of the leftmost character of its string argument.
The ORD() function can handle multi-byte characters. This is in contrast to the ASCII() function, which only handles single-byte (8 bit) characters.
How ASCII() Works in MariaDB
In MariaDB, ASCII() is a built-in string function that returns the numeric ASCII value of the leftmost character of its string argument.
The ASCII() function only works on 8 bit characters. To get the code for multi-byte characters, use the ORD() function instead.
MongoDB sort()
In MongoDB, the cursor.sort() method specifies the order in which the query returns matching documents.
The sort() method accepts a document that specifies the field to sort, and the sort order. The sort order can be either 1 for ascending or -1 for descending.
You can also specify { $meta: "textScore" } when doing $text searches, in order to sort by the computed textScore metadata in descending order.
MongoDB $orderBy
In MongoDB, the $orderBy query modifier sorts the results of a query in ascending or descending order.
$orderBy accepts a document that specifies the field to sort, and the sort order. The sort order can be either 1 for ascending or -1 for descending.
$orderBy has been deprecated in the mongo shell since v3.2. Use the cursor.sort() method instead.
MongoDB $sort
In MongoDB, the $sort aggregation pipeline stage sorts all input documents and returns them to the pipeline in sorted order.
MongoDB $switch
In MongoDB, the $switch aggregation pipeline operator evaluates a series of case expressions, and executes a specified expression only when a case expression evaluates to true.
MongoDB $mergeObjects
In MongoDB, the $mergeObjects aggregation pipeline operator combines multiple documents into a single document.
MongoDB $isArray
In MongoDB you can use the $isArray aggregation pipeline operator to check whether or not a value is an array.
It accepts any valid expression, and returns true if the expression is an array, false if it’s not.
MongoDB $literal
In MongoDB, the $literal aggregation pipeline operator returns a value without parsing.
It accepts any valid expression, and returns the unparsed expression.
The $literal operator can be useful for when you have a value that MongoDB could inadvertently interpret as an expression, but you don’t want it to.
For example, if you have a monetary amount that includes a dollar sign, MongoDB might inadvertently interpret that as a field name. You can use $literal to prevent MongoDB from interpreting such expressions.