POV-Ray : Newsgroups : povray.binaries.utilities : df3 SQLite virtual tables Server Time
31 Oct 2024 10:21:59 EDT (-0400)
  df3 SQLite virtual tables (Message 1 to 3 of 3)  
From: jr
Subject: df3 SQLite virtual tables
Date: 26 Aug 2017 14:16:00
Message: <59a1bae0@news.povray.org>
hi,

announcing the second tool of the 'df3 tools' project: 'df3vt', a
virtual table module for the SQLite db which exposes DF3 data files as
tables.

this initial release (version 0.1.0) has limitations: all tables are
read only (UPDATEs are silently ignored, as are INSERTs and DELETEs),
and "ORDER BY" clauses have no effect.  also, there is as yet no way of
getting the file's dimensions.  the next release will address these
shortcomings.

to build the extension you need SQLite version 3.8.7 or later, and the
df3 tools library (a copy was posted on Fri, 4 Aug 2017 01:23:03 +0100
with message id <5983be7a@news.povray.org>).

df3vt will build on 64-bit GNU/Linux systems, and should build on
Windows also (but I've no system to test).

example usage, assumes that 'spiral.df3' is in the current working
directory:

$ sqlite3
sqlite> .load /path/to/df3vt
sqlite> CREATE VIRTUAL TABLE df3 USING df3vt(file='spiral.df3');
sqlite> SELECT * FROM df3 WHERE z = 2;

any and all feedback, hints, tips, constructive criticism, will be welcomed.

enjoy, jr.


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From: jr
Subject: Re: df3 SQLite virtual tables
Date: 26 Aug 2017 14:19:22
Message: <59a1bbaa$1@news.povray.org>
hi,

On 26/08/2017 19:15, jr wrote:

oops, missed the attachment. :-(

enjoy, jr.


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Attachments:
Download 'df3vt-0.1.0.tar.gz' (17 KB)

From: jr
Subject: Re: df3 SQLite virtual tables
Date: 3 Sep 2017 17:00:27
Message: <59ac6d6b@news.povray.org>
hi,

announcing an updated version (0.1.2) of the 'df3vt', the virtual table
module for SQLite3 databases.  the SQL UPDATE statement is now
supported, meaning DF3 files can be written as well as read.

the source is attached.

the usage example assumes a working copy of 'spiral.df3' in the current
working directory:

$ sqlite3
sqlite> .header on
sqlite> .load /path/to/df3vt
sqlite> CREATE VIRTUAL TABLE t1
   ...> USING df3vt(file='spiral.df3', readonly='no');
sqlite> SELECT * FROM t1 WHERE v = 255;
x   y   z  v
25  25  2  255
sqlite> UPDATE t1 SET v = 0 WHERE x = 25 AND y = 25 AND z = 2;
sqlite3>

as always, all feedback, hints, tips and constructive criticism will be
welcomed.

enjoy, jr.


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Attachments:
Download 'df3vt-0.1.2.tar.gz' (17 KB)

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