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>Chapter 5. Alter data of a column</H1
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>We alter now the data of the column. Just give the new value as a parameter to the method hk_column::set_asstring().</P
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>Example 5-1. Alter data of a column</B
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>   1&nbsp;#include &#60;hk_classes.h&#62;
   2&nbsp;#include &#60;iostream&#62;
   3&nbsp;int main()
   4&nbsp;{
   5&nbsp;   hk_drivermanager* mydrivermanager = new hk_drivermanager();
   6&nbsp;   if (mydrivermanager==NULL) {cout &#60;&#60;"error creating mydrivermanager"&#60;&#60;endl;exit(1);}
   7&nbsp;   hk_connection* myconnection = mydrivermanager-&#62;new_connection("mysql");
   8&nbsp;   if (myconnection==NULL) {cout &#60;&#60;"error creating myconnection"&#60;&#60;endl;exit(1);}
   9&nbsp;   myconnection-&#62;set_host("localhost");
  10&nbsp;   myconnection-&#62;set_user("root");
  11&nbsp;   myconnection-&#62;set_password("mypasswd");
  12&nbsp;   myconnection-&#62;connect();
  13&nbsp;
  14&nbsp;   hk_database* mydatabase=myconnection-&#62;new_database("exampledb");
  15&nbsp;   if (mydatabase==NULL) {cout &#60;&#60;"error creating mydatabase"&#60;&#60;endl;exit(1);}
  16&nbsp;   hk_datasource* mydatasource= mydatabase-&#62;new_table("authors");
  17&nbsp;   if (mydatasource==NULL) {cout &#60;&#60;"error creating mydatasource"&#60;&#60;endl;exit(1);}
  18&nbsp;   mydatasource-&#62;enable();
  19&nbsp;
  20&nbsp;   hk_column* mycolumn = mydatasource-&#62;column_by_name("name");
  21&nbsp;   if (mycolumn==NULL) {cout &#60;&#60;"error getting column"&#60;&#60;endl;exit(1);}
  22&nbsp;   <FONT
COLOR="RED"
>mycolumn-&#62;set_asstring("my new data");</FONT
>
  23&nbsp;   <FONT
COLOR="RED"
>mydatasource-&#62;store_changed_data();</FONT
>
  24&nbsp;   delete mydrivermanager;
  25&nbsp;}</PRE
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>The method mydatasource-&#62;store_changed_data(); will store the changes. The data will also be stored when you
move the rowselector to another row (hk_datasource::goto_row()) or when you disable the datasource
(hk_datasource::disable()).</P
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