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CREATE TABLE test (id INTEGER PRIMARY KEY, name TEXT, value REAL);the column id becomes an alias for the internal rowid — the B-tree key itself. A query like WHERE id = 5 resolves to a direct B-tree search and scales O(log n). (I already wrote a TLDR piece about how B-trees work here.) The SQLite query planner documentation states: “the time required to look up the desired row is proportional to logN rather than being proportional to N as in a full table scan.” This is not an optimization. It is a fundamental design decision in SQLite’s query optimizer:
，这一点在搜狗输入法中也有详细论述
В Израиле одним словом оценили ход операции против Ирана14:58
伊朗现在的战术是减少弹道导弹发射数量以节省弹药，同时投入无人机、巡航导弹和较老式的弹道导弹。这需要相当强的协调能力，因为一千多公里距离无人机需要飞行6—7小时，巡航导弹也要飞行90分钟以上，弹道导弹则只需十几分钟。在美以防空探测、指挥系统陷入饱和状态，拦截系统全面启动、发射后，伊朗再发射霍拉姆沙赫尔、征服者-1/2等具备机动能力的先进导弹打击重点目标，会令美以反导系统顾此失彼。而原本导弹型号繁杂带来的后勤保障劣势此时反而成了优势，美以反导系统必须面对一堆不同速度、不同弹道轨迹的来袭导弹，耗费更多系统资源。
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