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https://issues.apache.org/jira/browse/CALCITE-222?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=16923011#comment-16923011
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Julian Hyde commented on CALCITE-222:
-------------------------------------
Not surprising. That repo is very old. We migrated the issues to Apache JIRA
(keeping the same numbers) so there's no reason to reference the old issues.
> User-defined table macros
> -------------------------
>
> Key: CALCITE-222
> URL: https://issues.apache.org/jira/browse/CALCITE-222
> Project: Calcite
> Issue Type: Bug
> Reporter: GitHub Import
> Priority: Major
> Labels: github-import
>
> A table macro is a function that gets executed at prepare time and that
> generates a relational expression. It can have arguments, as long as those
> arguments are constants. Views are a special case of table macros - they have
> no arguments, so can be invoked using the same syntax as regular tables.
> Table macros can be registered programmatically, using `Schema.add(String
> name, Function function)`, where function implements `TableMacro`.
> Or they can be declared in the schema, using a class that has an `eval`
> method (static or non-static) declared to return `Table` or a subclass, and
> that actually return an object that implements `TranslatableTable`. Like this:
> ```json
> {
> version: '1.0',
> schemas: [
> {
> name: 'ADHOC',
> functions: [
> {
> name: 'MAC',
> className: 'com.example.MyTableMacro'
> }
> ]
> }
> ]
> }
> ```
> ```java
> public class MyTableMacro {
> public Table eval(String s) {
> return new TranslatableTable() { ... };
> }
> }
> ```
> ```sql
> SELECT * FROM TABLE(adhoc.mac('a string'));
> ```
> ---------------- Imported from GitHub ----------------
> Url: https://github.com/julianhyde/optiq/issues/222
> Created by: [julianhyde|https://github.com/julianhyde]
> Labels:
> Created at: Wed Apr 02 08:15:22 CEST 2014
> State: closed
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