OpenEuphoria

1. eDBI is born, feedback wanted

• Posted by jeremy (admin) Aug 27, 2009
• 2373 views
• Last edited Aug 28, 2009

eDBI is born. Please see eDBI for more information. A quick run down here, though:

1. Allows a common API to many different database servers/clients.
2. Database drivers are loaded dynamically, allowing your application to work with database drivers you've never even seen before.
3. Database drivers are easily written and do not require any changes to eDBI or your application to make them work.
4. eDBI works with Euphoria types, for instance, when you perform a query that contains a varchar, integer, decimal and a date/time value, you will not get back all "string" sequences. You will get back a sequence, an integer, an atom and a datetime (from std/datetime.e). Further, when doing queries, you can use these types directly as well.

An example:

-- 
-- Example edbi use 
--  
 
include std/datetime.e 
include edbi/edbi.e 
 
sequence data = { 
    { "Ronald Mc'Donald", 29382, datetime:subtract(datetime:new(), 32, YEARS) }, 
    { "Super Man", 55555, datetime:new(1944, 5, 18) }, 
    { "Wonder Woman", 21232, datetime:new(1972, 9, 29) } 
} 
 
edbi:set_driver_path("drivers") 
edbi:db_handle dbh = edbi:open("sqlite3://example.db") 
 
edbi:execute("DROP TABLE people") 
edbi:execute("CREATE TABLE people (name VARCHAR(30), zip INTEGER, dob datetime)") 
 
for i = 1 to length(data) do 
    edbi:execute("INSERT INTO people VALUES (%s, %d, %D)", data[i]) 
end for 
 
edbi:dbr_handle dbr = edbi:query("SELECT * FROM people") 
 
object person 
while sequence(person) with entry do 
    printf(1, "Name=%s, Zip=%d, Dob=%s\n", {  
        person[1], person[2], datetime:format(person[3], "%m/%d/%Y") }) 
entry 
    person = edbi:next(dbr) 
end while 
 
edbi:close() 

Now, to make that work, on say, MySQL, just change the opening line to:

edbi:db_handle dbh = edbi:open("mysql://localhost?dbname=people") 

The same is true for any database driver that may exist.

What database drivers exist right now? Just the reference implementation, SQLite3. I am looking for help on other ones. The next highest priority is MySQL then PgSQL.

If you are interested in joining in on this project, please let me know.

Jeremy

3. Re: eDBI is born, feedback wanted

• Posted by jeremy (admin) Aug 29, 2009
• 2238 views
• Last edited Aug 30, 2009

Yes, SVN exists for Windows and most platforms. If you are a command line user, Setup-Subversion-1.6.5.msi will do the trick. If you like GUI clients, then you may want TortoiseSVN.

Right now, while eDBI is in heavy development, SVN will be the only real way to download it. Once it get's to a stable state, then I will start producing binaries.

Now, right now, if you wish to play with it, all you need is really 2 files: edbi.e and edbi_sqlite3.dll. That will enable you to start playing. You may also want to look at the example: example.ex to get some simple ideas. You can run eudoc -o edbi.txt edbi.ex to get full docs on it.

Oh, about 4.0. Yes, eDBI is for 4.0 only. 4.0 adds too many nice features to try and program for 4.0 and 3.1. Nothing I produce will be backward compatible with 3.1, it's just not worth it.

Jeremy

5. Re: eDBI is born, feedback wanted

• Posted by mattlewis (admin) Aug 29, 2009
• 2167 views
• Last edited Aug 30, 2009

Those are the URIs to the files in svn. They won't resolve using http. You need to use an svn client to either check them out or export.

Matt

7. Re: eDBI is born, feedback wanted

• Posted by jeremy (admin) Aug 30, 2009
• 2123 views

Matt, SVN will resolve just fine from a web browser. It's just a standard http/https request with GET/PUT actions.

Jeremy

9. Re: eDBI is born, feedback wanted

• Posted by sergelli Aug 30, 2009
• 2155 views

The address in the Open Wiki Euphoria
"http://jeremy.cowgar.com/svn/edbi/trunk edbi"
intended to be used with the "SVN"
Nor ok, This is the answer in "SVN"
---------------------------------------
URL
'http://jeremy.cowgar.com/svn/edbi/trunk%20edbi'
non-existent in that revision

11. Re: eDBI is born, feedback wanted

• Posted by consultjohan Oct 14, 2009
• 1991 views

Jeremy,

This is good stuff man! I'm trying it with mysql, and it works great.

Regards,

CJ

13. Re: eDBI is born, feedback wanted

• Posted by raseu Oct 14, 2009
• 1931 views
• Last edited Oct 15, 2009

great work,

poss mem leak in edbi_sqlite3.c ?

object __cdecl edbi_execute(object dbh, object sql) 
{ 
   sqlite3 *db = (sqlite3 *) dbh; 
   char *c_sql; 
   int result; 
                
   c_sql = EMalloc(SEQ_PTR(sql)->length + 1); 
   MakeCString(c_sql, sql, SEQ_PTR(sql)->length + 1); 
                         
   result = sqlite3_exec(db, c_sql, 0, 0, 0); 
   
   // MISSING EFree(c_sql); 
 
   return result; 
}  

15. Re: eDBI is born, feedback wanted

• Posted by euphoric (admin) Oct 14, 2009
• 1929 views
• Last edited Oct 15, 2009

How's that EuSQL plugin coming along?

17. Re: eDBI is born, feedback wanted

• Posted by euphoric (admin) Oct 15, 2009
• 1908 views

If you can get example_2.exw working, I'll try to take over from there.

19. Re: eDBI is born, feedback wanted

• Posted by euphoric (admin) Oct 15, 2009
• 1865 views

Well, there's a "bad routine number" problem I don't have time to diagnose. Maybe in the near future I can get at it.

21. Re: eDBI is born, feedback wanted

• Posted by jimcbrown (admin) Oct 15, 2009
• 1879 views

Hmm, ok, I downloaded http://downloads.sourceforge.net/project/eusql/eusql/v0.78.1/eusql-0-78-1-full.zip?use_mirror=voxel but that requires symeval.e which is missing???

23. Re: eDBI is born, feedback wanted

• Posted by jimcbrown (admin) Oct 15, 2009
• 1921 views

Ah, ok. I got matheval from http://downloads.sourceforge.net/project/matheval/matheval/v1.65/matheval-1-65.zip?use_mirror=voxel but then got the following ex.err:

eusql.e:7651 
<0074>:: Errors resolving the following references: 
	eusql.e (7651): db_rename_table 
 
	db_rename_table( table_name, new_name ) 
	               ^ 
 
Warning ( not_used ): 
	<0320>:: /opt/euphoria/include/machine.e - module variable 'check_calls' is assigned but never used 
 
--- Defined Words --- 
EU4 
EU400 
EU40000 
EUC 
EUC 
UNIX 
LINUX 
------------------- 

So I changed that to rename_table( db_name, table_name, new_name ) ... but at this point I'm wondering if eusql ever worked.

25. Re: eDBI is born, feedback wanted

• Posted by mattlewis (admin) Oct 15, 2009
• 1970 views

eusql.e:7651 
<0074>:: Errors resolving the following references: 
	eusql.e (7651): db_rename_table 
 
	db_rename_table( table_name, new_name ) 
	               ^ 

You've got an old version. Yes, it's the last released version, but it's pretty old. Even so, I can't see why db_rename_table() wouldn't work. It's in both database.e (which you'd be using) and std/eds.e (which the head uses).

I'd recommend using the latest from svn for each:

• https://eusql.svn.sourceforge.net/svnroot/eusql/trunk
• https://matheval.svn.sourceforge.net/svnroot/matheval/trunk

That code has been updated for version 4 of euphoria. Plus lots of other fixes. The eusql release is now about 50 revisions behind the head of the trunk. Since the main users of eusql have been me and CK, it hasn't been released as often as it probably should have.

Matt

27. Re: eDBI is born, feedback wanted

• Posted by jimcbrown (admin) Oct 15, 2009
• 1917 views

The real issue is that I seem to be missing example.db - so the edbi_open() call fails.

29. Re: eDBI is born, feedback wanted

• Posted by jimcbrown (admin) Oct 15, 2009
• 1856 views

Ok, so for the time being I've modified edbi.e to allow one to specify either a dll or a set of routine ids. So now I can just include edbi_eusql.e directly in example_2.ex, and create a list of routine ids, and it just works.

I discovered a bug in edbi_eusql.e, edbi_next() should take two paramenters (dbr and row) but only took one. After fixing this, I can uncomment the stuff in example_2.ex and it prints out a list of names.

$ eui -i drivers/eusql/matheval -i drivers/eusql/euslibs -i drivers/eusql/eusql example_2.ex 
edbi_open 
eumem:malloc() 
open_db 
returning from edbi_open: 2 
Name=Ronald Mc''Donald, Zip=29382, Dob=10/15/1977 
Name=Super Man, Zip=55555, Dob=05/18/1944 
Name=Wonder Woman, Zip=21232, Dob=09/29/1972 
$  

Forked into: Using native euphoria in edbi

31. Re: eDBI is born, feedback wanted

• Posted by mattlewis (admin) Oct 15, 2009
• 1848 views

This is fixed now. See ticket:99.

Matt

33. Re: eDBI is born, feedback wanted

• Posted by euphoric (admin) Oct 15, 2009
• 1841 views

Are you going to commit any changes?

35. Re: eDBI is born, feedback wanted

• Posted by consultjohan Oct 16, 2009
• 1861 views

For what it's worth, I'm trying to figure out how to

- get mysql_num_rows working. (I need to know how big to make my wxgrid)
- catch connection errors - I get a machine-level exception in edbi.e when I supply the wrong database password
- catch SQL errors. It brings down my whole application
- best work with fields of type date/datetime. (I'm not hardcoding field names in my application, so to get a date formated, I'll have to go and get metadata to see if there are date fields, and when populating the grid, I'll have to format the column as date/datetime in the row loop, which is inefficient and too much work)

What do you think?

37. Re: eDBI is born, feedback wanted

• Posted by consultjohan Oct 28, 2009
• 1740 views

Jeremy,

Thanks for the response. I managed to work around some issues with a small patch here and there. Thanks also for the advice. For example:

public type dbr_handle(object o) 
    if not atom(o) then return 0 end if 
    if o = 0 then return 1 end if 
 
    if error_code() then return 1 end if 
 
    integer l = length(ram_space) 
    object d = 0 
 
    if l >= o then 
        d = ram_space[o] 
    end if 
 
    if not sequence(d) then return 0 end if 
    if not length(d) = Q_END then return 0 end if 
 
    return 1 
end type 

Regards,

CJ