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https://issues.apache.org/jira/browse/CALCITE-111?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=17481160#comment-17481160
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ZheHu commented on CALCITE-111:
-------------------------------
Hi, [~julianhyde] . Based on your conversation in CALCITE-4014, I have two
questions about this issue:
# Does CONVERT function only work between two String value? I tried
convert(int_field using utf8) in mysql, which also succeeded.
# According to the java_doc, TRANSLATE works the same as CONVERT. Do we need
to implement those two funcs in this case(including test cases)? If yes, can we
add a new SqlKind like *CONVERT* on behalf of those two, instead of
OTHER_FUNCTION.
After my local test, I find the following steps might work:
* During validation, instead of identifier, treat and validate the param
Charset by SqlUtil.getCharset(charsetName), which only support corresponding
Standard Charsets in *java.nio.charset.Charset*.
* Add a ConvertImplementor in RexImpTable for the codegen of CONVERT/TRANSLATE
func.
If I understand this correctly, I'm happy to take this issue.
> Support CONVERT function, for changing character sets
> -----------------------------------------------------
>
> Key: CALCITE-111
> URL: https://issues.apache.org/jira/browse/CALCITE-111
> Project: Calcite
> Issue Type: Improvement
> Reporter: GitHub Import
> Priority: Major
> Labels: github-import
>
> Support the CONVERT function, to convert strings from one character set to
> another.
> CONVERT is defined in SQL:2011 as a feature called <character
> transliteration>. Here is an example:
> ```sql
> SELECT * FROM emp WHERE CONVERT(name USING UTF16) = u&'\82f1\56fd'
> ```
> The <a
> href="http://dev.mysql.com/doc/refman/5.0/en/charset-convert.html";>MySQL
> site</a> has other examples.
> ---------------- Imported from GitHub ----------------
> Url: https://github.com/julianhyde/optiq/issues/111
> Created by: [julianhyde|https://github.com/julianhyde]
> Labels: enhancement,
> Created at: Tue Jan 14 03:40:53 CET 2014
> State: open
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