Language
With CloudWatch Logs Insights, you use a query language to query your log groups. The query syntax supports different functions and operations that include but aren't limited to general functions, arithmetic and comparison operations, and regular expressions.
To create queries that contain multiple commands, separate the commands with the pipe character (|).
To create queries that contain comments, set off the comments with the hash character (#).
Language With CloudWatch Logs Insights, you use a query language to query your log groups. The query syntax supports different functions and operations that include but aren't limited to general functions, arithmetic and comparison operations, and regular expressions.
To create queries that contain multiple commands, separate the commands with the pipe character (|).
To create queries that contain comments, set off the comments with the hash character (#).
Additional resources
https://docs.aws.amazon.com/AmazonCloudWatch/latest/logs/CWL_QuerySyntax.html
Example highlight from AWS console: