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MySQL++ User Manual
}
// Build a query to retrieve the stock item that has Unicode
// characters encoded in UTF-8 form.
mysqlpp::Query query = con.query();
query << "select * from stock where item = \"Nürnberger Brats\"";
// Retrieve the row, throwing an exception if it fails.
mysqlpp::Result res = query.store();
if (res.empty()) {
throw mysqlpp::BadQuery("UTF-8 bratwurst item not found in "
"table, run resetdb");
}
// Because there should only be one row in the result set,
// there's no point in storing the result in an STL container.
// We can store the first row directly into a stock structure
// because one of an SSQLS's constructors takes a Row object.
stock row = res.at(0);
// Create a copy so that the replace query knows what the
// original values are.
stock orig_row = row;
// Change the stock object's item to use only 7-bit ASCII, and
// to deliberately be wider than normal column widths printed
// by print_stock_table().
row.item = "Nuerenberger Bratwurst";
// Form the query to replace the row in the stock table.
query.update(orig_row, row);
// Show the query about to be executed.
cout << "Query: " << query.preview() << endl;
// Run the query with execute(), since UPDATE doesn't return a
// result set.
query.execute();
// Print the new table contents.
get_stock_table(query, res);
print_stock_rows(res);
}
catch (const mysqlpp::BadQuery& er) {
// Handle any query errors
cerr << "Query error: " << er.what() << endl;
return -1;
}
catch (const mysqlpp::BadConversion& er) {
// Handle bad conversions
cerr << "Conversion error: " << er.what() << endl <<
"\tretrieved data size: " << er.retrieved <<
", actual size: " << er.actual_size << endl;
return -1;
}
catch (const mysqlpp::Exception& er) {
// Catch-all for any other MySQL++ exceptions
cerr << "Error: " << er.what() << endl;
return -1;
}
return 0;
}
When you run the example you will notice that in the WHERE clause only the 'item' field is checked for. This is because SSQLS also also less-than-comparable.
Don't forget to run resetdb after running the example.
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