Support columns for temporary table

[kou]

Use cases:

• Named output columns in select like "AS" in SQL

  • Creating a column to temporary table and assigning return value
    of function to the column:

    select --filter all_records() \
           --column[snippet].type ShortText \
           --column[snippet].value 'snippet_html(body)' \
           --output_columns _id,snippet
    

• Drilldown by computed value

  • Select -> Create temporary column -> Compute value -> Drilldown:

    select --filter all_records()
    --column[year].type UInt8
    --column[year].value 'time_to_year(updated_at)'
    --drilldown year