Shall I use Special Characters in Firebase Param Value “event_params.value.string_value” & query in Bigquery?

Question

In Firebase it is clearly mentioned that \"Param values can be up to 100 characters long. The \"firebase_\", \"google_\" and \"ga_\" prefixes are reserved and should not be used

Answer 1

The documentation you referenced clearly specify requirements for parameter's name and value - so obviously you must comply

Params supply information that contextualize Events. You can associate up to 25 unique Params with each Event type. Some Params are suggested below for certain common Events, but you are not limited to these. You may supply extra Params for suggested Events or custom Params for Custom events. Param names can be up to 40 characters long, may only contain alphanumeric characters and underscores (""), and must start with an alphabetic character. Param values can be up to 100 characters long. The "firebase", "google_" and "ga_" prefixes are reserved and should not be used.

Meantime, those limitations have nothing to do with BigQuery
So, if you are dealing with non-firebase data - feel free to use all those chars

P.S. the best recommendation I can give for such cases - try by your own and you will see. It is so easy and fast to get this type of questions answered!