特朗普在会上还宣布成立一个“全新的军事联盟”，目标是彻底消灭在西半球肆虐的“贩毒集团和恐怖网络”。（央视新闻）
.unwrap_or_else(|| "unknown".to_string());，推荐阅读新收录的资料获取更多信息
The planner is still using the sequential plan. Only the estimated number of rows has changed. Why? If you remember from previous article, it's where column level statistics come into play. Histogram bounds still match the original 10,000 rows we inserted.，推荐阅读新收录的资料获取更多信息
case_sensitive: bool = false,。新收录的资料对此有专业解读