[jira] [Closed] (CALCITE-4841) Support decimal column type in CSV and File adapter

["Rui Wang (Jira)" <ji...@apache.org>]

     [ https://issues.apache.org/jira/browse/CALCITE-4841?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]

Rui Wang closed CALCITE-4841.
-----------------------------

> Support decimal column type in CSV and File adapter
> ---------------------------------------------------
>
>                 Key: CALCITE-4841
>                 URL: https://issues.apache.org/jira/browse/CALCITE-4841
>             Project: Calcite
>          Issue Type: Improvement
>          Components: csv-adapter, file-adapter
>            Reporter: Louis Kuang
>            Priority: Minor
>              Labels: pull-request-available
>             Fix For: 1.29.0
>
>          Time Spent: 3h 20m
>  Remaining Estimate: 0h
>
> Currently, the csv adapter does not support the decimal/numeric column type (see supported types in [CsvFieldType|https://github.com/apache/calcite/blob/4bc916619fd286b2c0cc4d5c653c96a68801d74e/file/src/main/java/org/apache/calcite/adapter/file/CsvFieldType.java#L35]. Any type that is not supported will be interpreted by the [CsvEnumerator|https://github.com/apache/calcite/blob/master/file/src/main/java/org/apache/calcite/adapter/file/CsvEnumerator.java] as string.
> When dealing with decimal numbers, the currently most appropriate type is `double`. However, this is not accurate enough for financial data. This feature request proposes adding a `decimal` column type that will be implemented by the Java `BigDecimal` type (and by conversion in [JavaToSqlTypeConversionRules|https://github.com/apache/calcite/blob/4bc916619fd286b2c0cc4d5c653c96a68801d74e/core/src/main/java/org/apache/calcite/sql/type/JavaToSqlTypeConversionRules.java#L74] be represented as a `Decimal` SQL type). This allow financial data to be represented and computed more accurately (`BigDecimal` has higher precision than `double`).
> Please see sample implementation in PR.
> Context: I am trying to leverage Calcite to add some SQL support to [ledger|https://www.ledger-cli.org/] reporting. 



--
This message was sent by Atlassian Jira
(v8.20.1#820001)