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Urgent help! CdaoDatabase add multiple new fields ...

Posted on 2000-02-26
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Last Modified: 2013-11-20
Hi,

I have created a new database as specified by user, then i want to insert new fields (together with values got from an old database). i use the following code:(outline)

// create the new database
if (!createDatabase(&m_newDatabase, m_newDatabaseName))
    m_newDatabase = NULL;

// read values from old one and add them to the new one
for (i=0;i<count;i++){

......
  // add/create  new fields
   openDatabase(m_newDatabase, m_strDatabaseName, FALSE);      
   strcpy(sql_add,"CREATE TABLE DataTab (");
   strcat(sql_add,fd_name);
   strcat(sql_add," CHAR(10))");
   m_newDatabase->Execute(sql_add);       
   m_newDatabase->Close();

   m_strTableName="DataTab";
   openDatabase(m_newDatabase, m_newDatabaseName, FALSE);
  openTableDef(m_newDatabase,&m_newTableDef,                         m_strTableName);

  // open a recordset for the new database
  CDaoRecordset rs1(m_newDatabase);            
  rs1.Open(m_newTableDef);

  //open a recordset for the old database
  openDatabase(&m_oldDatabase, m_oldDatabaseName, FALSE);
  openTableDef(m_oldDatabase, &m_oldTableDef, m_strTableName);
  CDaoRecordset rs(m_oldDatabase);            
  rs.Open(m_pTableDef);
 // read values from old one and add them to the new one
 ....
  rs1.AddNew();
  rs1.SetFieldValue(field_name,age_str);
  rs1.Update();

}


my problem is :

for the first time i add ONE new field, it works; but later on if i did not delete the newly created databse, and if i continue to add new filed(s) (even to another new database), it says:

the DataTab already exists...

i use the same table name for the old and new database...

any one has any idea? pls help me!!!! i need to solve it urgently!!!!

thanks a million!!!!

0
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Question by:greenbird
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8 Comments
 
LVL 3

Expert Comment

by:V_Bapat
ID: 2569143
Why don't you split the job into 2 parts?

1. Create tables & fields.
2. Copy records.

This will make it easy.

I have code to copy all the tables which I can give you.
0
 

Author Comment

by:greenbird
ID: 2571130
Hi,

where is ur code? :) u can email to :
aibinbin@hotmail.com...

i think in my another post, u answered my qn rite? i post new thing there, pls check it out...

thanks a lot for ur greate help! really appreciate it..
0
 
LVL 3

Accepted Solution

by:
V_Bapat earned 20 total points
ID: 2571761
This function copies all the tables. All the tables should already be created before calling this function.

So you have to write a function to create all the tables and create the fields.

CopyTables()
{
      COleVariant covFieldValue;
      CString strTableName;
      int nTableCount, i, j, nFieldCount;
      CDaoTableDefInfo pTableInfo;
      
      CDaoDatabase* m_pSrcDatabase = NULL;
      CDatabase::OpenDatabase(&m_pSrcDatabase, m_strDbName);
      
      CDaoRecordset m_pSrc(m_pSrcDatabase);
      CDaoRecordset m_pDest(m_pDatabase);
      
      nTableCount = m_pDatabase->GetTableDefCount();
      
      for(j = 0; j < nTableCount; j++)
      {
            m_pDatabase->GetTableDefInfo(j, pTableInfo);

            if(pTableInfo.m_lAttributes & dbSystemObject | pTableInfo.m_lAttributes & dbHiddenObject)
                  continue;

            m_strSQL = CString("SELECT * FROM ") + pTableInfo.m_strName;
            
            m_pSrc.Open(dbOpenDynaset, m_strSQL);
            m_pSrc.MoveFirst();
            m_pDest.Open(dbOpenDynaset, m_strSQL);
            
            nFieldCount = m_pSrc.GetFieldCount();
            
            while(!m_pSrc.IsEOF())
            {
                  m_pDest.AddNew();
                  for(i = 0; i < nFieldCount; i++)
                  {
                        m_pSrc.GetFieldValue(i, covFieldValue);
                        m_pDest.SetFieldValue(i, covFieldValue);
                  }
                  m_pDest.Update();
                  m_pDest.MoveLast();
                  m_pSrc.MoveNext();
            }
            
            m_pSrc.Close();
            m_pDest.Close();
      }

      CDatabase::CloseDatabase(&m_pSrcDatabase);
}

Vicky

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Author Comment

by:greenbird
ID: 2572677
Hi, Vicky,

thanks a lot! i will try it tomorrow.. but could u pls refer to my another post: add field problem also, i have some qns there waiting for ur help... thanks a lot!
0
 
LVL 3

Expert Comment

by:V_Bapat
ID: 2586484
greenbird
I was out of town for last 4 days. I will try it today.

What about this one. Did you try it?

Vicky
0
 

Author Comment

by:greenbird
ID: 2586620
Hi, V_bapat,

no wonder why u did not help me .. :) now feel good that u will help me :) i need to solve it by tomorrow....
Thanks a lot!
0
 

Author Comment

by:greenbird
ID: 2586621
Adjusted points to 20
0
 

Author Comment

by:greenbird
ID: 2587153
Hi,

sovle it already :))) thanks a lot for ur help!
0

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