SQLite field keeps only half of the data
lazarus / 16-Databases

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atasoft · 2011-07-17 13:38

I am actually developing my first database project in Lazarus using
SQLite3 database. I used the SQLite Administrator to create the
database.

Problem:
If I insert 50 character length english data in a varchar(50) field
everything is okey, but if I insert 50 character length greek data or
50 non-english characters of any language (German, Czech, etc.) only
the first 25 characters are inserted in the database.

I can solve my problem if I set the length of fields in double of its
size but this is not a professional solution.
Surely the problem is the character set. it must be unicode.
How can I solve the above problem? Any idea?

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jixian.yang · 2011-07-17 15:32

The patch for a stable version of database component:
http://bugs.freepascal.org/view.php?id=17376

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jixian.yang · 2011-07-17 15:35

Or use Zeoslib, it is free and supports more database and supports
Storedproc .
By using Zeoslib we can change database without changing components.

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jixian.yang · 2011-07-17 15:37

And it can be used without freepascal recompilation.

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atasoft · 2011-07-17 20:53

Thanks all of you. I forgot to mention that I am using
ZEOSDBO-6.6.6-stable components. Anyway I have the problem on both
SQLdb and Zeos.

Using database tool Lita or SQLite Sorcerer or Sqliteman I can fill
the full size of the field (e.g 50) using greek or english characters
without problem. Using my application I can read all the 50 english
characters but only the first 25 GREEK characters. Therefore the
problem has to do with the configuration of the connection component
(SOMETHING TO SET UNICODE CHARACTER SET) or  it is something wrong
with the lazarus Data Controls components (does they support
unicode?).

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atasoft · 2011-07-17 22:13

I installed the Zeos components in Delphi 6 and I developed a small
application using the zeos components  and I connected to the same
sqlite database. Now everything works perfectly. I did NOT configure
the zeos connection component to unicode character. The Zeos
components works ok in Delphi. (Note that the Greek characters that I
insert in database using Lazarus application are "chinese" in Delphi
application and the opposite).

Therefore the problem seems to be with  the Lazarus Database Controls
components. It seems that they do NOT support unicode. How can I solve
the above problem? I do not want to rewrite the whole application in
delphi.

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atasoft · 2011-07-17 23:08

Workaround for the problem is to use the functions Utf8encode and
UTF8decode. I tested them and they really work. But I have to use them
for all the varchar fields. That means that really the Lazarus Data
Controls does not support unicode. Is it any better solution?

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jixian.yang · 2011-07-18 09:40

Quote from: atasoft on July 18, 2011, 12:13:32 amI installed the Zeos
components in Delphi 6 and I developed a small application using the
zeos components  and I connected to the same sqlite database. Now
everything works perfectly. I did NOT configure the zeos connection
component to unicode character. The Zeos components works ok in
Delphi. (Note that the Greek characters that I insert in database
using Lazarus application are "chinese" in Delphi application and the
opposite).

It works fine in Delphi 6, that means the data stored in SQLite3
database is  not UTF8.

You can transform the data by UTF8Encode(data) and insert it into
database. Then the data will be correctly retrieved.