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https://issues.apache.org/jira/browse/DRILL-57?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13633942#comment-13633942
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Michael Hausenblas commented on DRILL-57:
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OK, so I took that over. Though I *think* I know the current codebase I'd
appreciate directions where and how to start this.
> Add a logical operator that returns a constant result, similar to VALUES
> operator in SQL
> ----------------------------------------------------------------------------------------
>
> Key: DRILL-57
> URL: https://issues.apache.org/jira/browse/DRILL-57
> Project: Apache Drill
> Issue Type: Bug
> Reporter: Julian Hyde
> Assignee: Michael Hausenblas
>
> Add a logical operator that returns a constant result. This is necessary to
> be able to create values out of thin air, if you don't know what tables exist.
> This operator is analogous to the VALUES operator in SQL. For example,
> VALUES (1, 'a'), (2, 'b'), (3, 'c')
> returns 2 rows with 3 columns and
> VALUES (1, 'a'), (2, 'b'), (3, 'c') AS t(c1, c2)
> allows you to name those columns "c1" and "c2". VALUES is useful for
> evaluating expressions that don't belong in a table, for example
> VALUES 10 + 3
> (Some databases would express this "SELECT 10 + 3". Same idea, and same
> underlying relational operator.)
> The JSON for this new operator might look like this:
> {
> op: "constant",
> content: { [
> {c1: 1, c2: "a"},
> {c1: 2, c3: ["x", "y", "z"]}
> ] }
> }
> This operator is necessary in order to implement the SQL VALUES clause.
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