#include... WT_CURSOR *cursor; int ret; // Open a table ret = conn->open_cursor(session, "mytable", NULL, NULL, &cursor); if (ret != 0) { // Handle error } // Traverse all rows in the table while ((ret = cursor->next(cursor)) == 0) { // Get the key and value for the current row const char *key; const char *value; ret = cursor->get_key(cursor, &key); ret = cursor->get_value(cursor, &value); // Process the key/value pair } // Close the cursor cursor->close(cursor);
#includeThis example shows how to use a cursor within a transaction to modify rows in a table. It opens a transaction with `begin_transaction`, opens a cursor over a table named "mytable", and uses the `next` method to iterate over the rows in the table. For each row, it retrieves the key and value with the `get_key` and `get_value` methods, modifies the value with a custom function `modify_value`, and updates the row with the new value using the `set_value` method. Finally, it commits the transaction with `commit_transaction` and closes the cursor. Package/library: WiredTiger... WT_CURSOR *cursor; int ret; // Open a transaction ret = conn->begin_transaction(session, NULL); if (ret != 0) { // Handle error } // Open a cursor over a table ret = conn->open_cursor(session, "mytable", NULL, NULL, &cursor); if (ret != 0) { conn->abort_transaction(session, NULL); // Handle error } // Traverse rows in the table within the transaction while ((ret = cursor->next(cursor)) == 0) { // Get the key and value for the current row const char *key; const char *value; ret = cursor->get_key(cursor, &key); ret = cursor->get_value(cursor, &value); // Modify the value const char *newvalue = modify_value(value); // Update the row with the new value ret = cursor->set_value(cursor, newvalue); } // Commit the transaction ret = conn->commit_transaction(session, NULL); if (ret != 0) { conn->abort_transaction(session, NULL); // Handle error } // Close the cursor cursor->close(cursor);