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What is the motivation?

I wanted to insert multiple records, but if the key exists to update the existing record with a specific update for each insertion. I thought Upsert would a be suitable canidate, but Upsert weirdly mimics Update and it does not allow multiple record upsertions at once. I didnt want to rewrite the Upsert from ground up, so I decided just to adjust INSERT statement. So, I can define for each record I am inserting a compatible update (or not).
The implementation was heavily motivated for usage in sdks, have less request/ not having to use raw sql code, to archive big data Operations.

What does this change do?

It extends the capability of ON DUPLICATE KEY UPDATE.
@field =@value will still work and corresponds to: for all inserts this change will be implemneted if it already exists.

[{@field =@value, ... },...] can now also be used: each index of the array correponds to the index of the inserts

• if one index should have no updates just leave it emtpy [{@field =@value, ... }, {}, {@field =@value, ... }]
• if only one is provided it will default to one update for all insert
• the index matching requires the array to have the same number of 'updates' of records as the number of records to be inserted (except if length is one)

What is your testing strategy?

added tests

Is this related to any issues?

• No related issues

Does this change need documentation?

surrealdb/docs.surrealdb.com#1227

Have you read the Contributing Guidelines?

Yes, I have read theContributing Guidelines