Kikyou1997 opened a new pull request, #9303: URL: https://github.com/apache/incubator-doris/pull/9303
# Proposed changes Issue Number: #9242 ## Problem Summary: This PR is a part of code of supports for global dict. To support global dict, we need to have someway to let BE gathering and merge all the local dict to a global one, so when everytime the DictManager initial builds or updates a column dict,it will send a SQL like this: ```sql SELECT dict(d_date) FROM date [META]; ``` As above sample shows, we added a new hint `META` and a new special aggregate function named `dict`. In analyze phase, we will check if there is a hint named `META`, if there is, this stmt will be marked as a meta scan query. For such stmt, we will generate MetaScanNode in Planner instead of OlapScanNode, and the column referenced by SlotRef in the function parameters will be add to MetaScanNode's `slotIdToDictId` field with Map type which be will generate global dict for, the value represents the dict_id which is always -1 for now it wil be used for the incremental update of column dict in BE in the future. ## Checklist(Required) 1. Does it affect the original behavior: (Yes) 2. Has unit tests been added: (No) 3. Has document been added or modified: (No Need) 4. Does it need to update dependencies: (No) 5. Are there any changes that cannot be rolled back: (No) ## Further comments If this is a relatively large or complex change, kick off the discussion at [d...@doris.apache.org](mailto:d...@doris.apache.org) by explaining why you chose the solution you did and what alternatives you considered, etc... -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For queries about this service, please contact Infrastructure at: us...@infra.apache.org --------------------------------------------------------------------- To unsubscribe, e-mail: commits-unsubscr...@doris.apache.org For additional commands, e-mail: commits-h...@doris.apache.org
