Illuminate\Database\Connection::update PHP Method

    public function update($query, $bindings = [])
    {
        return $this->affectingStatement($query, $bindings);
    }

 /**
  * Update a record in the database.
  *
  * @param  array  $values
  * @return int
  */
 public function update(array $values)
 {
     $sql = $this->grammar->compileUpdate($this, $values);
     return $this->connection->update($sql, $this->cleanBindings($this->grammar->prepareBindingsForUpdate($this->bindings, $values)));
 }