template <int N>
struct sqlbuffN
{ char bf[N];
  char * p;
  sqlbuffN() { clear(); }

  operator const char *() const { return bf; }
  void clear() { p=bf; *p=0; }
  void set(const char *s) { strcpy(bf,s); p=bf+strlen(s); }
  sqlbuffN & operator < (int i)
  { p+=sprintf(p,"%d",i); return *this; }
  sqlbuffN & operator <= (int i)
  { p+=sprintf(p,"%d",i); return *this; }
  sqlbuffN & operator < (const char * cp)
  { strcpy(p,cp); p+=strlen(p); return *this; }
  sqlbuffN & operator <= (const char * cp)
  { p+=sqlQuote(p,cp); return * this;}
  sqlbuffN & operator < (const std::string & s) { return *this<(s.c_str()); }
  sqlbuffN & operator <=(const std::string & s) { return *this<=(s.c_str()); }

};



struct sqlbuff
{ mem_buffer bf;
  int off;
  
  explicit sqlbuff(int sz = 4096)
  { bf.resize(sz,0); }
  void clear() { off=0; }

  sqlbuff & operator <(const char * txt)
  { int len = strlen(txt);
    bf.growto2(off+len+1,mem_buffer::copydata);
    strcpy(bf.p+off,txt); off+=len;
    return *this;
  }
  sqlbuff & operator <= (const char * txt)
  { int len = 2*strlen(txt)+2;
    bf.growto2(off+len+1,mem_buffer::copydata);
    off+=sqlQuote(bf.p+off,txt);
    return * this;
  }
  sqlbuff & operator < (const std::string & s) { return *this<(s.c_str()); }
  sqlbuff & operator <=(const std::string & s) { return *this<=(s.c_str()); }
  
  

  sqlbuff & operator < (int i)
  { bf.growto2(off+15,mem_buffer::copydata); off+=sprintf(bf.p+off,"%d",i); return *this; }
  sqlbuff & operator <= (int i)
  { bf.growto2(off+15,mem_buffer::copydata); off+=sprintf(bf.p+off,"%d",i); return *this; }
  
  operator const char *() const { return bf.p; }
};

really simple sql buffer

C++