pIdx->azColl[0] = p->aCol[i].zColl;
      }
    }
  }else{
    sqlite3DbFree(db, zColl);
  }
}

/*
** This function returns the collation sequence for database native text
** encoding identified by the string zName, length nName.
**
** If the requested collation sequence is not available, or not available
** in the database native encoding, the collation factory is invoked to
** request it. If the collation factory does not supply such a sequence,
** and the sequence is available in another text encoding, then that is
** returned instead.
**
** If no versions of the requested collations sequence are available, or
** another error occurs, NULL is returned and an error message written into
** pParse.
**
** This routine is a wrapper around sqlite3FindCollSeq().  This routine
** invokes the collation factory if the named collation cannot be found
** and generates an error message.
**
** See also: sqlite3FindCollSeq(), sqlite3GetCollSeq()
*/
CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName){
  sqlite3 *db = pParse->db;
  u8 enc = ENC(db);
  u8 initbusy = db->init.busy;
  CollSeq *pColl;

  pColl = sqlite3FindCollSeq(db, enc, zName, initbusy);
  if( !initbusy && (!pColl || !pColl->xCmp) ){
    pColl = sqlite3GetCollSeq(pParse, enc, pColl, zName);
  }

  return pColl;
}


/*
** Generate code that will increment the schema cookie.
**
** The schema cookie is used to determine when the schema for the
** database changes.  After each schema change, the cookie value
** changes.  When a process first reads the schema it records the

        pIdx->azColl[0] = p->aCol[i].zColl;
      }
    }
  }else{
    sqlite3DbFree(db, zColl);
  }
}




































/*
** Generate code that will increment the schema cookie.
**
** The schema cookie is used to determine when the schema for the
** database changes.  After each schema change, the cookie value
** changes.  When a process first reads the schema it records the

      pColl->xDel = 0;         /* Do not copy the destructor */
      return SQLITE_OK;
    }
  }
  return SQLITE_ERROR;
}

/*
** This function is responsible for invoking the collation factory callback
** or substituting a collation sequence of a different encoding when the
** requested collation sequence is not available in the desired encoding.
** 
** If it is not NULL, then pColl must point to the database native encoding 
** collation sequence with name zName, length nName.
**
** The return value is either the collation sequence to be used in database
** db for collation type name zName, length nName, or NULL, if no collation
** sequence can be found.  If no collation is found, leave an error message.
**
** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
*/
CollSeq *sqlite3GetCollSeq(
  Parse *pParse,        /* Parsing context */
  u8 enc,               /* The desired encoding for the collating sequence */
  CollSeq *pColl,       /* Collating sequence with native encoding, or NULL */
  const char *zName     /* Collating sequence name */
){
  CollSeq *p;
  sqlite3 *db = pParse->db;

  p = pColl;
  if( !p ){
    p = sqlite3FindCollSeq(db, enc, zName, 0);
  }
  if( !p || !p->xCmp ){
    /* No collation sequence of this type for this encoding is registered.
    ** Call the collation factory to see if it can supply us with one.
    */
    callCollNeeded(db, enc, zName);
    p = sqlite3FindCollSeq(db, enc, zName, 0);
  }
  if( p && !p->xCmp && synthCollSeq(db, p) ){
    p = 0;
  }
  assert( !p || p->xCmp );
  if( p==0 ){
    sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
    pParse->rc = SQLITE_ERROR_MISSING_COLLSEQ;
  }
  return p;
}

/*
** This routine is called on a collation sequence before it is used to
** check that it is defined. An undefined collation sequence exists when
** a database is loaded that contains references to collation sequences
** that have not been defined by sqlite3_create_collation() etc.
**
** If required, this routine calls the 'collation needed' callback to
................................................................................
** this routine.  sqlite3LocateCollSeq() invokes the collation factory
** if necessary and generates an error message if the collating sequence
** cannot be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3GetCollSeq()
*/
CollSeq *sqlite3FindCollSeq(
  sqlite3 *db,
  u8 enc,
  const char *zName,
  int create
){
  CollSeq *pColl;
  if( zName ){
    pColl = findCollSeqEntry(db, zName, create);
  }else{
    pColl = db->pDfltColl;
  }
  assert( SQLITE_UTF8==1 && SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
  assert( enc>=SQLITE_UTF8 && enc<=SQLITE_UTF16BE );
  if( pColl ) pColl += enc-1;















































































  return pColl;
}

/* During the search for the best function definition, this procedure
** is called to test how well the function passed as the first argument
** matches the request for a function with nArg arguments in a system
** that uses encoding enc. The value returned indicates how well the

      pColl->xDel = 0;         /* Do not copy the destructor */
      return SQLITE_OK;
    }
  }
  return SQLITE_ERROR;
}














































/*
** This routine is called on a collation sequence before it is used to
** check that it is defined. An undefined collation sequence exists when
** a database is loaded that contains references to collation sequences
** that have not been defined by sqlite3_create_collation() etc.
**
** If required, this routine calls the 'collation needed' callback to
................................................................................
** this routine.  sqlite3LocateCollSeq() invokes the collation factory
** if necessary and generates an error message if the collating sequence
** cannot be found.
**
** See also: sqlite3LocateCollSeq(), sqlite3GetCollSeq()
*/
CollSeq *sqlite3FindCollSeq(
  sqlite3 *db,          /* Database connection to search */
  u8 enc,               /* Desired text encoding */
  const char *zName,    /* Name of the collating sequence.  Might be NULL */
  int create            /* True to create CollSeq if doesn't already exist */
){
  CollSeq *pColl;
  if( zName ){
    pColl = findCollSeqEntry(db, zName, create);
  }else{
    pColl = db->pDfltColl;
  }
  assert( SQLITE_UTF8==1 && SQLITE_UTF16LE==2 && SQLITE_UTF16BE==3 );
  assert( enc>=SQLITE_UTF8 && enc<=SQLITE_UTF16BE );
  if( pColl ) pColl += enc-1;
  return pColl;
}

/*
** This function is responsible for invoking the collation factory callback
** or substituting a collation sequence of a different encoding when the
** requested collation sequence is not available in the desired encoding.
** 
** If it is not NULL, then pColl must point to the database native encoding 
** collation sequence with name zName, length nName.
**
** The return value is either the collation sequence to be used in database
** db for collation type name zName, length nName, or NULL, if no collation
** sequence can be found.  If no collation is found, leave an error message.
**
** See also: sqlite3LocateCollSeq(), sqlite3FindCollSeq()
*/
CollSeq *sqlite3GetCollSeq(
  Parse *pParse,        /* Parsing context */
  u8 enc,               /* The desired encoding for the collating sequence */
  CollSeq *pColl,       /* Collating sequence with native encoding, or NULL */
  const char *zName     /* Collating sequence name */
){
  CollSeq *p;
  sqlite3 *db = pParse->db;

  p = pColl;
  if( !p ){
    p = sqlite3FindCollSeq(db, enc, zName, 0);
  }
  if( !p || !p->xCmp ){
    /* No collation sequence of this type for this encoding is registered.
    ** Call the collation factory to see if it can supply us with one.
    */
    callCollNeeded(db, enc, zName);
    p = sqlite3FindCollSeq(db, enc, zName, 0);
  }
  if( p && !p->xCmp && synthCollSeq(db, p) ){
    p = 0;
  }
  assert( !p || p->xCmp );
  if( p==0 ){
    sqlite3ErrorMsg(pParse, "no such collation sequence: %s", zName);
    pParse->rc = SQLITE_ERROR_MISSING_COLLSEQ;
  }
  return p;
}

/*
** This function returns the collation sequence for database native text
** encoding identified by the string zName.
**
** If the requested collation sequence is not available, or not available
** in the database native encoding, the collation factory is invoked to
** request it. If the collation factory does not supply such a sequence,
** and the sequence is available in another text encoding, then that is
** returned instead.
**
** If no versions of the requested collations sequence are available, or
** another error occurs, NULL is returned and an error message written into
** pParse.
**
** This routine is a wrapper around sqlite3FindCollSeq().  This routine
** invokes the collation factory if the named collation cannot be found
** and generates an error message.
**
** See also: sqlite3FindCollSeq(), sqlite3GetCollSeq()
*/
CollSeq *sqlite3LocateCollSeq(Parse *pParse, const char *zName){
  sqlite3 *db = pParse->db;
  u8 enc = ENC(db);
  u8 initbusy = db->init.busy;
  CollSeq *pColl;

  pColl = sqlite3FindCollSeq(db, enc, zName, initbusy);
  if( !initbusy && (!pColl || !pColl->xCmp) ){
    pColl = sqlite3GetCollSeq(pParse, enc, pColl, zName);
  }

  return pColl;
}

/* During the search for the best function definition, this procedure
** is called to test how well the function passed as the first argument
** matches the request for a function with nArg arguments in a system
** that uses encoding enc. The value returned indicates how well the