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https://issues.apache.org/jira/browse/SIS-180?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14161359#comment-14161359
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Martin Desruisseaux commented on SIS-180:
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I wonder, if the first version limit itself to the {{SELECT * FROM <table>}}
clause, I wonder if we could start with a manually-written parser instead than
using AntLR? I find tools that generate code automatically useful for a quick
start, but later become a limitation. For example Sun initially written javac
using such tools, and later abandoned it and rewrote the full javac parser from
scratch, manually. I had myself similar experience with the Well Known Text
(WKT) parser: the first version wrote 10 years ago was using something like
AntLR, and later we had to abandon it and rewrite everything from scratch. I
believe that as the text that we are tying to parse gains in complexity, the
constraint of such tools become more problematic.
> Place a crude JDBC driver over Dbase files
> ------------------------------------------
>
> Key: SIS-180
> URL: https://issues.apache.org/jira/browse/SIS-180
> Project: Spatial Information Systems
> Issue Type: Improvement
> Components: Storage
> Affects Versions: 0.5
> Reporter: M. Le Bihan
> Priority: Minor
>
> It would be useful to be able to query DBF content through SQL.
> But there are no free drivers available for the old _Dbase 3_ format.
> The first step is to create short implementations of _Connection_,
> _Statement_, _ResultSet_, _ResultSetMetadata_ interfaces for a JDBC using our
> _Database_ class as core binary loader at the begining.
> The main difficulty is to respond to a SQL request, and first : being able to
> analyze it to understand what is expected.
> The SQL request analysis is a very strong job, but I suggest to ease it a lot
> by relying on _AntLR_ API for grammar analysis, associated with a BNF grammar
> file, maybe taken from ^1^ or from elsewhere (grammars are of public domain).
> The goal of this current JIRA is only to be able to perform a
> _SELECT * FROM <shapefile layer name>_
> The WHERE clause or the selection of fields, will come later in other JIRA.
> No transactions, classic _Statement_ only.
> _PreparedStatement_ would be also implemented later (another JIRA).
> Of course, this improvment can be discarded if an open source or free driver
> is discovered, that would allow us to execute SQL requests on DBase 3 easily.
> ^1^ For example, [http://www.savage.net.au/SQL/] has some BNF, but maybe
> elsewhere they will more compliant with AntLR.
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