索引 · PHP知识汇总

![](https://img.kancloud.cn/f3/56/f3567df021422d7b19ddb8a60c908e73_736x237.png) ![](https://img.kancloud.cn/4d/ef/4def140b4edbe871ac6338b1bfdf6f11_535x232.png) ![](https://img.kancloud.cn/58/b5/58b5e7ea33f6e3d6678ee55f315227fb_730x236.png) 降低写的速度，占磁盘空间 ![](https://img.kancloud.cn/6c/7c/6c7c81399ed69e93e18dabb6749d6ce0_615x193.png) ![](https://img.kancloud.cn/a9/b4/a9b4c12e6ca2ba3fba1f0379f9abaf4d_729x272.png) ![](https://img.kancloud.cn/c4/2a/c42a8bdd94566a0bb1354c947cbb2706_727x398.png) ![](https://img.kancloud.cn/9d/94/9d94f29492c0614af43f3e2d2c5d65f1_730x195.png) 联合必须是连续的， abc，ab, a 管用的， ![](https://img.kancloud.cn/1a/42/1a42ac91eacce3aedc1790a11717a544_683x254.png) ![](https://img.kancloud.cn/a3/88/a388a07415faae171dc375f4c17ea802_726x90.png)