What problem does this PR solve?

Issue Number: close #xxx

Related PR: #xxx

Problem Summary:

For routine load jobs, if we have thousands of columns to import, we can use json format let doris automatically match the column name with table schema. But for some scenarios, the upstream data does not have the column name(can be derived from current columns) and we can not add new column name easily, so we consider if we can just specify the new derived column only and let doris fill the missing columns with table schema.

e.g.

The MQ data have stat_time_day field but does not have p_date column, we can add new column like this p_date = stat_time_day, fill missing columns from table schema.

CREATE ROUTINE LOAD db.job_name ON table_a
COLUMNS(p_date = stat_time_day)
PROPERTIES (
    "format" = "json",
    "fill_missing_columns" = "true"
)
FROM KAFKA (...);

Release note

None

Check List (For Author)

• Test

  • Regression test
  • Unit Test
  • Manual test (add detailed scripts or steps below)
  • No need to test or manual test. Explain why:
    • This is a refactor/code format and no logic has been changed.
    • Previous test can cover this change.
    • No code files have been changed.
    • Other reason

• Behavior changed:

  • No.
  • Yes.

• Does this need documentation?

  • No.
  • Yes.

Check List (For Reviewer who merge this PR)

• Confirm the release note
• Confirm test cases
• Confirm document
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