How to use insertOnDuplicate query in Magento 2.

Use of insertOnDuplicate query using Magento 2,  You need to create a Connection object first to run the query using ResourceConnection class.

When you insert any new row into a table if the row causes a duplicate in the Primary key or UNIQUE index, throw an error in MySQL.

Base Definition of function:

/**
 * Inserts a table row with specified data.
 *
 * @param mixed $table The table to insert data into.
 * @param array $data Column-value pairs or array of column-value pairs.
 * @param array $fields update fields pairs or values
 * @return int The number of affected rows.
 */
public function insertOnDuplicate($table, array $data, array $fields = []);

Example,