How to emulate ElasticSearch ignore_above clause in MySQL?-CodePudding

I am migrating from ElasticSearch to MySQL. My current ElasticSearch is using "ignore_above" : 256 for some fields.

Checking documentation https://www.elastic.co/guide/en/elasticsearch/reference/current/ignore-above.html

Strings longer than the ignore_above setting will not be indexed or stored.

How to accurately emulate this on (My)SQL level? Is there other option than TRIGGER that

checks length of given field
replaces the value with empty value if length>256?

CodePudding user response：

ignore_above: 256 means that if the length of your field is more than 256 it won't be searchable (indexed or stored), but still would be possible to return it in _source field.

All strings/array elements will still be present in the _source field, if the latter is enabled which is the default in Elasticsearch.

To have the same behavior in MySQL you would still need to store the value of the field in your table as a TEXT because you eventually want to return the value if it is matching the id of your document for example.