Saving text in Sqlite3, c++ - c++

Question

here is my second post in the community, excuse me if I'm forget to add something, just let me know:
I am trying to do a program in c++ able to save text (i want to save code) in a database using sqlite3. Currently I've made a wxWidget program that call some functions from a DLL and this ones interactuate with the database.
The database that I want to make is really simple, it has 3 columns in one table (id,name, ref). My problem comes when I want to save big amount of text that also contains simblos that can conflict with the sql queries (I would like to save files inside the database, for example in the "ref" column ).
I'm using mostly the sqlite3_exec function, because the functions sqlite3_prepare_v2, sqlite_bind, sqlite3_step crash me the DLL where I'm working.
My doubt: Can I directly save any text as big as I want, without taking care about if it has simbols or not? and how can I do it?.
More info: I am working in c++ with code:block(13.12) making a DLL of sqlite3 functions and using MinGW toolchain. (windows 7).
This is an example of an insert function that I'm using:
int DLL_EXPORT add_item(sqlite3* db, string tbname,string col,string item)
{
char* db_err = 0;
if (tbname==std::string()||col==std::string()||item==std::string())
throw std::invalid_argument( "stoi: invalid argument table name");
char buf[200];
sprintf(buf,"insert into %s (%s) values ('%s');", tbname.c_str(), col.c_str(),item.c_str());
int n = sqlite3_exec(db, buf, NULL, 0, &db_err);
dsperr(&db_err);
if( n != SQLITE_OK )
{
//throw something
}
return 0;
}
Thank you in advance.

Answer 1

Thank to CL. for the up commentary
// Add one text to a table
// The column must be specify
//
int DLL_EXPORT add_text(sqlite3* db, string tbname,string col,string id,string item)
{
char* db_err = 0;
if (tbname==std::string()||col==std::string()||item==std::string())
throw std::invalid_argument( "stoi: invalid argument table name");
char *zSQL = sqlite3_mprintf("UPDATE %q SET %q=(%Q) WHERE id=%q", tbname.c_str(),col.c_str() ,item.c_str(),id.c_str());
int n = sqlite3_exec(db, zSQL, NULL, 0, &db_err);
dsperr(&db_err);
sqlite3_free(zSQL);
if( n != SQLITE_OK )
{
// throw something
}
return 0;
}