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https://issues.apache.org/jira/browse/IMPALA-7896?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Paul Rogers resolved IMPALA-7896.
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Resolution: Fixed
> Literals should not need explicit analyze step
> ----------------------------------------------
>
> Key: IMPALA-7896
> URL: https://issues.apache.org/jira/browse/IMPALA-7896
> Project: IMPALA
> Issue Type: Improvement
> Components: Frontend
> Affects Versions: Impala 3.0
> Reporter: Paul Rogers
> Assignee: Paul Rogers
> Priority: Minor
>
> The Impala FE has the concept of a _lteral_ (string, boolean, null, number.)
> Originally, literals could only be created as part of the AST. Hence, all
> literals are subclasses of {{LiteralExpr}} which are {{ExprNodes}}. The
> analysis step is used to set the type of the literal numbers, when not known
> at create time. If literals were used only in the AST, this would be fine,
> they could be analyzed with an analyzer.
> In fact, as the code has evolved, {{LiteralExpr}} nodes are created via the
> catalog, which has no analyzer. To fudge the issue, the
> {{LiteralExpr.create()}} function does analysis with a null analyzer. This,
> in turn, means that the {{analyze()}} code needs to special case a null
> analyzer. This, in turn, leads to brittle, error prone code.
> Since literals are immutable (except, sadly, for type), it is better that
> they start analyzed. Since the only attribute which must be set is the type,
> and the type can be known at create time, we have the {{analyze()}} be an
> optional no-op, leading to cleaner semantics.
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