World: r3wp

I am confused about what driver is doing ... the difference of Direct 
mode. Hmm, maybe I do - there is a difference between the string 
mode, and block mode. With string mode, the driver does not touch 
the expression, so I am responsible for putting VALUES('06-Dec-2006') 
or VALUES('"06-Dec-2006"') - simply put - if I want in db to have 
my date value being represented as a REBOL string, I have to put 
it into parenthesis myself. So actually parenthesing it twice, as 
sqlite itself already uses '06-Dec-2006' and considers it being a 
string ...

Maybe there is a bug with block mode?

Does block mode do datatype conversions? Perhaps there is a type 
mismatch.

CONNECT %test.db

SQL "drop table t"
SQL "create table t (c)"

SQL "insert into t values ('Word')"
SQL {insert into t values ('"String"')}
SQL ["insert into t values (?)" 'Word]
SQL ["insert into t values (?)" "String"]

test1: SQL "select * from t"

DISCONNECT

CONNECT/direct %test.db

SQL "drop table t"
SQL "create table t (c)"

SQL "insert into t values ('String')"
SQL ["insert into t values (?)" "String"]

test2: SQL "select * from t"

DISCONNECT

ok, so how can I explain to  mysel data corruption? It is reproducable. 
should I set type of fields when creating tables? Or should I create 
tables in external tool?

Petr, I had the same problem. There is a RAMBO ticket and Ashley 
posted his findings about it.

I use the SQLite command line tool for batch importing.

Pekr, "... Ashley posted his findings about it ...", refer post of 
7th Nov in this group.


Note that it works fine if you use the direct refinement, but then 
you won't have access to the full range of REBOL data types. Also 
note that you can use IMPORT instead of a foreach loop, as in:

	IMPORT statement values

Success! ... of sorts. If you add a 'recycle as the first line of 
the 'sql func then all seems to work fine; but a lot slowwwwwwer 
(1 minute 48 as opposed to 1.5 seconds in Pekr's test case).


But, if you recycle every 100 statements it still works and only 
increases the runtime to 1.85 seconds. I'll do a few more tests before 
uploading a new version with this change.

1.0.2 available at: http://www.dobeash.com/download.html


Workaround to RAMBO#4063. Seems to work with Pekr's and my test cases 
after several thousand runs without error.

Pekr, the import statement for your script would look like:

	sqlite/import "insert into logs values (?,?,?,?,?,?)" log-info


and is about twice as fast as the foreach loop (and now works correctly 
under 1.0.2).

beer-client-loop: func [/local last-mem mem-jetzt ports-bak] [
    recycle/off 
    last-mem: stats 
    forever [
        if error? set/any 'error try [
            wait 0.1
        ] [
            write %autsch.txt mold disarm error 
            win-log 
            print "-----------------" 
            print disarm error
        ] 
        if 20 * 1000 * 1000 + last-mem < mem-jetzt: stats [
            recycle 
            last-mem: stats 

            /print [now/time mem-jetzt - last-mem mem-jetzt last-mem]
        ]
    ]
]

that saved my script, which uses beer and heavy blitting

maybe that methods helps in your case too.

There seems to be a bit messy situation in how integers are handled 
with SQLite, so beware. If you don't specify column types, as eg. 
in my following example:

create table logs (date, time, ipaddr, url, ctype, incident)

, then expect following situation:

1) sql "select incident from logs where incident = 4"   ; works

2) sql ["select incident from logs where incident = ?" 4]  ; works

3) sql "select incident from logs where incident = '4'"   ;  does 
not work


The strange thing is, that editing my db in SQLiteAdmin, it shows 
not column types (but imo it has to choose some "default" type internally). 
Changing according field type to Integer type, makes above case number 
3) to work too ...


So maybe it is always better to not be lazy and specify precisely 
column types? But in fact, when I specified column type as Integer, 
I did NOT expect case 3 to work ... I am going to do more tests myself 
to save myself from later headaches during specifying more complicated 
queries :-)

Be sure to read "Manifest typing" at http://www.sqlite.org/different.html

Petr, yes I have seen some effects of these as well. But didn't tracked 
them further down yet.

I read "manifest typing" and it is strange - even if you set your 
column as an integer, it allows you to enter non-integer data ...

That's cool!! One of SQLite big advantages. Why should I be forced 
to tell the type upfront?

There is just no need for this. The DB should store each cell most 
efficient.

what do you use for typical rebol strings, or even dates? text? varchar?

I never specify anything. Only for INTEGER

that has a bit of a bad effect for sqladmin grid ... if you don't 
specify field type or length, it lists one collumn wide thru all 
the screen ...

Question: I have something like a bill-of-material. And I would like 
to get such a structure back as graph. I'm just thinking of this 
isn't a generic function suitable to be coupled with a database. 
What do you think?

Robert - what do you mean as a graph? A hieararchical structure?

I have good link, although it relates to mySQL - it shows how to 
query hierarchical data - http://dev.mysql.com/tech-resources/articles/hierarchical-data.html

yes, most likely but with the possibility to have cycles etc.

Thx for the link. As always, good references Petr. You should make 
your money with answers.google.com

and of course having more than one parent.

heh, never heard of answers.google.com ... well, maybe that is why 
I would like to work as a consultant, hopefully with IBM ... the 
bad thing is, that I might miss programming a bit :-)

as for real graphs with relational model storage - that is beyond 
my understanding .... hopefull article might give you some pointers 
...

It's worth tracking down some of Joe Celko's articles on the issue 
too.
http://www.ibase.ru/devinfo/DBMSTrees/sqltrees.html

I'm thinking about updating to the newest SQLite version. And I just 
read there is a new API which should be used.


The sqlite3_prepare_v2() and sqlite3_prepare16_v2() interfaces are 
recommended for all new programs. The two older interfaces are retained 
for backwards compatibility, but their use is discouraged. In the 
"v2" interfaces, the prepared statement that is returned (the sqlite3_stmt 
object) contains a copy of the original SQL. This causes the sqlite3_step() 
interface to behave a differently in two ways:


If the database schema changes, instead of returning SQLITE_SCHEMA 
as it always used to do, sqlite3_step() will automatically recompile 
the SQL statement and try to run it again. If the schema has changed 
in a way that makes the statement no longer valid, sqlite3_step() 
will still return SQLITE_SCHEMA. But unlike the legacy behavior, 
SQLITE_SCHEMA is now a fatal error. Calling sqlite3_prepare_v2() 
again will not make the error go away. Note: use sqlite3_errmsg() 
to find the text of the parsing error that results in an SQLITE_SCHEMA 
return. 


When an error occurs, sqlite3_step() will return one of the detailed 
result-codes like SQLITE_IOERR or SQLITE_FULL or SQLITE_SCHEMA directly. 
The legacy behavior was that sqlite3_step() would only return a generic 
SQLITE_ERROR code and you would have to make a second call to sqlite3_reset() 
in order to find the underlying cause of the problem. With the "v2" 
prepare interfaces, the underlying reason for the error is returned 
directly.

Ashley, are you working on an update to SQLite.r at the moment?

How long will the old API exist?

I don't know.

btw - do you use collation for the german language?

No, just the plain version.

are you working on an update to SQLite.r at the moment?

 I didn't even know they had changed the API! If it's an easy change 
 I'll do it sooner than later.

one more link related to trees in mysql: http://www.artfulsoftware.com/mysqlbook/sampler/mysqled1ch20.html

Will, thx for the link.

Ashley, it looks mostly compatible to me, just the returned errors 
are a bit different.

1.0.3 available at: http://www.dobeash.com/download.html

Supports latest SQLite v2 API.

*** WARNING ***
Is not compatible with older versions of the SQLite DLL.

Great! I'll give it a try with a new DLL.

http://www.sqlite.org/

2007-Jun-18 - Version 3.4.0


  This release fixes two separate bugs either of which can lead to 
  database corruption. Upgrading is strongly recommended.

is there any solution, how to infuence shell window appearance, if 
using sqlite3.exe? There seems to be no silent mode ... you can start 
sqlite3.exe and type .help to see more comands, or look here:

http://www.die.net/doc/linux/man/man1/sqlite3.1.html

1.0.4 available at: http://www.dobeash.com/download.html


Mac OS X version 10.4 support added as per http://developer.apple.com/documentation/MacOSX/Conceptual/OSX_Technology_Overview/AppTechnology/chapter_5_section_20.html

Our Sqlite docs say: "2.3.3 Fkeys - This refinement returns information 
about the foreign keys (if any) that reference a table.", but sqlite 
does not support foreign-keys, only via triggers, no?

hmm, sqlite does not provide insert or update facility, that is weak 
:-(

it has insert or replace = replace, but that deletes original record 
and replaces it with new, probably changing row id, so no facility 
like insert .... on duplicate key update .....