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Prefix to prevent name clash in SQL: SqlId, variables, tables, ... [message #14170]

Sun, 17 February 2008 13:40

mingodad
Messages: 53
Registered: February 2008
Location: Spain

Member

Today I was converting one application to upp 2008.1 and found that the actual system of parse database schema can generate name clash:

TABLE_(CURRENCIES)
INT_ (CURRENCY)
END_TABLE

The above will generate a name clash:
----------
main.cpp
In file included from d:\upp\uppsrc/Sql/sch_model.h:162,
from d:\upp\uppsrc/plugin/sqlite3/Sqlite3Schema.h:82,
from d:\upp\uppsrc/Sql/sch_header.h:45,
from d:\MyApps\DADBiz\/DADBiz.h:17,
from d:\MyApps\DADBiz\main.cpp:1:
d:\MyApps/DADBiz/dadbiz.sch:33: error: 'Upp::SqlId CURRENCY' redeclared as different kind of symbol
d:\upp\mingw\include/oaidl.h:113: error: previous declaration of 'typedef union CY CURRENCY'
In file included from d:\upp\uppsrc/Sql/sch_model.h:162,
from d:\upp\uppsrc/plugin/sqlite3/Sqlite3Schema.h:82,
from d:\upp\uppsrc/Sql/sch_source.h:6,
from d:\MyApps\DADBiz\/DADBiz.h:18,
from d:\MyApps\DADBiz\main.cpp:1:
d:\MyApps/DADBiz/dadbiz.sch:33: error: 'Upp::SqlId CURRENCY' redeclared as different kind of symbol
d:\upp\mingw\include/oaidl.h:113: error: previous declaration of 'typedef union CY CURRENCY'
----------
[FEATURE REQUEST]
So I studied the source code and end up with some modifications that allow us to specify a prefix to the generated symbols with a definition of one preprocessor macro:

#define SCHEMA_PREFIX_CPP _ANY_PREFIX_YOU_LIKE_

And after that any reference to tables or fields should be done as:

dbList.AddKey(_ANY_PREFIX_YOU_LIKE_CURRENCY);
dbList.SetTable(_ANY_PREFIX_YOU_LIKE_CURRENCIES);
dbList.AddColumn(_ANY_PREFIX_YOU_LIKE_CURRENCY, t_("Id"), Cool

.SetFormat("%8>d");
dbList.SetOrderBy(_ANY_PREFIX_YOU_LIKE_CURRENCY).Limit(100);

It doesn't break any application that already works, because without defining SCHEMA_PREFIX_CPP all generated symbols remain as before.

In this process I've found a bug in GCC when joining string in macros, in some cases it adds a space betwen the tokens, that's why the macro ADD_SCHEMA_PREFIX_CPP2 was created.

I've sending attached the files I've modified.

I'll hope it will be usefull to others and probably be included in the official distribution too !

Thanks for all of you that help develop this fantastic tool !

If you need more explanations, ask me !

Ps:
[FEATURE REQUEST]
As well to allow applications made with upp to work with databases, tables generated by other programs that doesn't create table and record fields names in uppercase (commonly lowercase) a patch to sql.cpp to make comparisons after convert field names retrieved fron queries to upper case.

Instead of:
// sql.cpp line 254
Value Sql::operator[](SqlId id) const {
String s = ~id;
for(int i = 0; i < cn->info.GetCount(); i++)
if(cn->info[i].name == s)
return operator[](i);
return Value();
}

Use this :

Value Sql::operator[](SqlId id) const {
String s = ~id;
for(int i = 0; i < cn->info.GetCount(); i++)
{
String sb = ToUpper(cn->info[i].name);
if(sb == s)
return operator[](i);
}
return Value();
}

Attachment: sch_header.h
(Size: 1.66KB, Downloaded 430 times)
Attachment: sch_model.h
(Size: 3.76KB, Downloaded 459 times)
Attachment: sch_source.h
(Size: 3.62KB, Downloaded 708 times)
Attachment: Sql.cpp
(Size: 15.26KB, Downloaded 559 times)

[Updated on: Tue, 19 February 2008 22:10]

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