{"id":10007060,"date":"2023-01-10T12:25:10","date_gmt":"2023-01-10T04:25:10","guid":{"rendered":"https:\/\/ityet.com\/?p=10007060"},"modified":"2023-01-10T12:25:10","modified_gmt":"2023-01-10T04:25:10","slug":"redis%e7%9a%84string%e7%b1%bb%e5%9e%8b%ef%bc%8c%e5%8e%9f%e6%9d%a5%e8%bf%99%e4%b9%88%e5%8d%a0%e5%86%85%e5%ad%98","status":"publish","type":"post","link":"https:\/\/itmax.cn\/?p=10007060","title":{"rendered":"Redis\u7684String\u7c7b\u578b\uff0c\u539f\u6765\u8fd9\u4e48\u5360\u5185\u5b58"},"content":{"rendered":"

Redis\u7684String\u7c7b\u578b\uff0c\u539f\u6765\u8fd9\u4e48\u5360\u5185\u5b58<\/h2>\n

\u5b58\u4e00\u4e2a Long \u7c7b\u578b\u8fd9\u4e48\u5360\u5185\u5b58\uff0cRedis \u7684\u5185\u5b58\u5f00\u9500\u90fd\u82b1\u5728\u54ea\u513f\u4e86\uff1f<\/p><\/blockquote>\n

1\u3001\u573a\u666f\u4ecb\u7ecd<\/h3>\n

\u5047\u8bbe\u73b0\u5728\u6211\u4eec\u8981\u5f00\u53d1\u4e00\u4e2a\u56fe\u7247\u5b58\u50a8\u7cfb\u7edf\uff0c\u8981\u6c42\u8fd9\u4e2a\u7cfb\u7edf\u80fd\u591f\u6839\u636e\u56fe\u7247 ID \u5feb\u901f\u67e5\u627e\u5230\u56fe\u7247\u5b58\u50a8\u5bf9\u8c61 ID\u3002\u56fe\u7247 ID \u548c\u56fe\u7247\u5b58\u50a8\u5bf9\u8c61 ID \u7684\u6837\u4f8b\u6570\u636e\u5982\u4e0b\uff1a<\/p>\n

photo_id: 1101000060\nphoto_obj_id: 3302000080<\/code><\/pre>\n
\u5728\u8fd9\u79cd\u573a\u666f\u4e0b\uff0c\u56fe\u7247 ID \u548c\u56fe\u7247\u5b58\u50a8\u5bf9\u8c61 ID \u521a\u597d\u662f\u4e00\u5bf9\u4e00\u7684\u5173\u7cfb\uff0c\u662f\u5178\u578b\u7684\u201c\u952e – \u5355\u503c\u201d\u6a21\u5f0f\uff0cRedis \u7684 String \u7c7b\u578b\u63d0\u4f9b\u4e86\u201c\u4e00\u4e2a\u952e\u5bf9\u5e94\u4e00\u4e2a\u503c\u7684\u6570\u636e\u201d\u7684\u4fdd\u5b58\u5f62\u5f0f\uff0c\u5728\u8fd9\u79cd\u573a\u666f\u4e0b\u521a\u597d\u9002\u7528\u3002<\/p>\n
\u786e\u5b9a\u4f7f\u7528 String \u7c7b\u578b\u540e\uff0c\u63a5\u4e0b\u6765\u6211\u4eec\u901a\u8fc7\u5b9e\u6218\uff0c\u6765\u770b\u770b\u5b83\u7684\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\u3002\u9996\u5148\u901a\u8fc7\u4e0b\u9762\u547d\u4ee4\u8fde\u63a5\u4e0a Redis\u3002<\/p>\n
\u672c\u6587\u6211\u4f7f\u7528\u7684 Redis Server \u53ca\u4e0b\u6587\u6e90\u7801\u90fd\u662f 6.2.4 \u7248\u672c\u3002<\/p><\/blockquote>\n
redis-cli -h 127.0.0.1 -p 6379<\/code><\/pre>\n
\u7136\u540e\u6267\u884c\u4e0b\u9762\u7684\u547d\u4ee4\u67e5\u770b Redis \u7684\u521d\u59cb\u5185\u5b58\u4f7f\u7528\u60c5\u51b5\u3002<\/p>\n
127.0.0.1:6379> info memory\n# Memory\nused_memory:871840<\/code><\/pre>\n
\u63a5\u7740\u63d2\u5165 10 \u6761\u6570\u636e\uff1a<\/p>\n
10.118.32.170:0> set 1101000060 3302000080\n10.118.32.170:0> set 1101000061 3302000081\n10.118.32.170:0> set 1101000062 3302000082\n10.118.32.170:0> set 1101000063 3302000083\n10.118.32.170:0> set 1101000064 3302000084\n10.118.32.170:0> set 1101000065 3302000085\n10.118.32.170:0> set 1101000066 3302000086\n10.118.32.170:0> set 1101000067 3302000087\n10.118.32.170:0> set 1101000068 3302000088\n10.118.32.170:0> set 1101000069 3302000089<\/code><\/pre>\n
\u518d\u6b21\u67e5\u770b\u5185\u5b58\uff1a<\/p>\n
127.0.0.1:6379> info memory\n# Memory\nused_memory:872528<\/code><\/pre>\n
\u53ef\u4ee5\u770b\u5230\uff0c\u5b58\u50a8 10 \u4e2a\u56fe\u7247\uff0c\u5185\u5b58\u4f7f\u7528\u4e86 688 \u4e2a\u5b57\u8282\u3002\u4e00\u4e2a\u56fe\u7247 ID \u548c\u56fe\u7247\u5b58\u50a8\u5bf9\u8c61 ID \u7684\u8bb0\u5f55\u5e73\u5747\u7528\u4e86 68 \u5b57\u8282\u3002<\/p>\n
\u4f46\u95ee\u9898\u662f\uff0c\u4e00\u7ec4\u56fe\u7247 ID \u53ca\u5176\u5b58\u50a8\u5bf9\u8c61 ID \u7684\u8bb0\u5f55\uff0c\u5b9e\u9645\u53ea\u9700\u8981 16 \u5b57\u8282\u5c31\u53ef\u4ee5\u4e86\u3002\u56fe\u7247 ID \u548c\u56fe\u7247\u5b58\u50a8\u5bf9\u8c61 ID \u90fd\u662f 10 \u4f4d\u6570\uff0c\u800c 8 \u5b57\u8282\u7684 Long \u7c7b\u578b\u6700\u5927\u53ef\u4ee5\u8868\u793a 2 \u7684 64 \u6b21\u65b9\u7684\u6570\u503c\uff0c\u80af\u5b9a\u53ef\u4ee5\u8868\u793a 10 \u4f4d\u6570\u3002\u8fd9\u6837\u7b97\u4e0b\u6765\u53ea\u9700 16 \u5b57\u8282\u5c31\u53ef\u4ee5\u4e86\uff0c\u4e3a\u4ec0\u4e48 String \u7c7b\u578b\u5374\u7528\u4e86 68 \u5b57\u8282\u5462\uff1f<\/p>\n
\u4e3a\u4e86\u4e00\u63a2\u7a76\u7adf\uff0c\u6211\u4eec\u4e0d\u5f97\u4e0d\u4ece String \u7c7b\u578b\u7684\u5e95\u5c42\u5b9e\u73b0\u6252\u8d77\u3002<\/p>\n
2\u3001String \u7c7b\u578b\u7684\u5e95\u5c42\u5b9e\u73b0<\/h3>\n
\u5f53\u4f60\u4fdd\u5b58\u7684\u6570\u636e\u4e2d\u5305\u542b\u5b57\u7b26\u65f6\uff0cString \u7c7b\u578b\u5c31\u4f1a\u7528\u7b80\u5355\u52a8\u6001\u5b57\u7b26\u4e32\uff08Simple Dynamic String\uff0cSDS\uff09\u7ed3\u6784\u4f53\u6765\u4fdd\u5b58\u3002<\/p>\n
2.1 SDS<\/h4>\n
SDS \u7684\u7ed3\u6784\u5b9a\u4e49\u5728sds.h<\/code>\u6587\u4ef6\u4e2d\uff0c\u5728 Redis 3.2 \u7248\u672c\u4e4b\u540e\uff0cSDS \u7531\u4e00\u79cd\u6570\u636e\u7ed3\u6784\u53d8\u6210\u4e86 5 \u79cd\u6570\u636e\u7ed3\u6784\u3002<\/p>\n
\/* Note: sdshdr5 is never used, we just access the flags byte directly.\n * However is here to document the layout of type 5 SDS strings. *\/\nstruct __attribute__ ((__packed__)) hisdshdr5 {\n    unsigned char flags; \/* 3 lsb of type, and 5 msb of string length *\/\n    char buf[];\n};\nstruct __attribute__ ((__packed__)) hisdshdr8 {\n    uint8_t len; \/* used *\/\n    uint8_t alloc; \/* excluding the header and null terminator *\/\n    unsigned char flags; \/* 3 lsb of type, 5 unused bits *\/\n    char buf[];\n};\nstruct __attribute__ ((__packed__)) hisdshdr16 {\n    uint16_t len; \/* used *\/\n    uint16_t alloc; \/* excluding the header and null terminator *\/\n    unsigned char flags; \/* 3 lsb of type, 5 unused bits *\/\n    char buf[];\n};\nstruct __attribute__ ((__packed__)) hisdshdr32 {\n    uint32_t len; \/* used *\/\n    uint32_t alloc; \/* excluding the header and null terminator *\/\n    unsigned char flags; \/* 3 lsb of type, 5 unused bits *\/\n    char buf[];\n};\nstruct __attribute__ ((__packed__)) hisdshdr64 {\n    uint64_t len; \/* used *\/\n    uint64_t alloc; \/* excluding the header and null terminator *\/\n    unsigned char flags; \/* 3 lsb of type, 5 unused bits *\/\n    char buf[];\n};<\/code><\/pre>\n
\u8fd9 5 \u79cd\u6570\u636e\u7ed3\u6784\u4f9d\u6b21\u5b58\u50a8\u4e0d\u540c\u957f\u5ea6\u7684\u5185\u5bb9\uff0cRedis \u4f1a\u6839\u636e SDS \u5b58\u50a8\u7684\u5185\u5bb9\u957f\u5ea6\u6765\u9009\u62e9\u4e0d\u540c\u7684\u7ed3\u6784\u3002<\/p>\n