<\/span><\/h2>\n\n\n\nINSTR(str,substr) \nINSTR(str,substr,start_position)\nINSTR(str,substr,start_position,nth_appearance)<\/code><\/pre>\n\n\n\n<\/span>\u8bf4\u660e<\/span><\/h2>\n\n\n\n\u5982\u679c\u627e\u5230\uff0c\u8fd4\u56de\u4ece\u5de6\u5f00\u59cb\u7684\u4f4d\u7f6e\uff0c\u4ece1\u5f00\u59cb\uff0c\u4e0d\u533a\u5206\u67e5\u627e\u65b9\u5411\uff1b\u5982\u679c\u6ca1\u627e\u5230\uff0c\u8fd4\u56de0\u3002<\/p>\n\n\n\n
- str \uff1a \u88ab\u67e5\u627e\u7684\u539f\u59cb\u5b57\u7b26\u4e32\u3002<\/li>
- substr \uff1a \u67e5\u627e\u7684\u5185\u5bb9\u3002<\/li>
- start_position \uff1a \u67e5\u627e\u5f00\u59cb\u7684\u4f4d\u7f6e\uff0c\u4ece\u5de6\u9762\u7b2c\u51e0\u4e2a\u5b57\u7b26\u5f00\u59cb\u5339\u914d\u3002\u5982\u679c\u662f\u8d1f\u6570\uff0c\u5219\u4ece\u53f3\u5411\u5de6\u5339\u914d\u3002\u9ed8\u8ba4\u4e3a1\u3002<\/li>
- nth_appearance \uff1a\u4ece start_position \u5f00\u59cb\u5411\u5b57\u7b26\u4e32\u5c3e\u65b9\u5411\u67e5\u627e\u7b2c\u51e0\u4e2a\u5339\u914d\u5b57\u7b26\u4e32\u3002\u53ef\u9009\u53c2\u6570\uff0c\u9ed8\u8ba4\u4e3a 1\u3002<\/li><\/ul>\n\n\n\n
<\/span>\u6837\u4f8b<\/span><\/h2>\n\n\n\n<\/span>\u666e\u901a\u67e5\u627e<\/span><\/h3>\n\n\n\n\u8fd4\u56de\u5176\u51fa\u73b0\u7684\u5b57\u7b26\u4f4d\u7f6e\u3002\u4ece1\u5f00\u59cb\u3002<\/p>\n\n\n\n
gbase> select instr('1234567890','1');\n+-------------------------+\n| instr('1234567890','1') |\n+-------------------------+\n| 1 |\n+-------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('1234567890','5');\n+-------------------------+\n| instr('1234567890','5') |\n+-------------------------+\n| 5 |\n+-------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u67e5\u627e\u4e0d\u5b58\u5728\u7684\u5b57\u7b26<\/span><\/h3>\n\n\n\n\u8fd4\u56de0\u3002<\/p>\n\n\n\n
gbase> select instr('1234567890','a');\n+-------------------------+\n| instr('1234567890','a') |\n+-------------------------+\n| 0 |\n+-------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u67e5\u627e\u7a7a\u5b57\u7b26\u4e32<\/span><\/h2>\n\n\n\n\u8fd4\u56de1\u3002<\/p>\n\n\n\n
gbase> select instr('1234567890','',1,30);\n+-----------------------------+\n| instr('1234567890','',1,30) |\n+-----------------------------+\n| 1 |\n+-----------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u67e5\u627eNULL<\/span><\/h3>\n\n\n\n\u8fd4\u56deNULL.\u6ce8\u610f\u4e0d\u662f0\u3002<\/p>\n\n\n\n
gbase> select instr('1234567890',null);\n+--------------------------+\n| instr('1234567890',null) |\n+--------------------------+\n| NULL |\n+--------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u6307\u5b9a\u8d77\u59cb\u4f4d\u7f6e<\/span><\/h3>\n\n\n\n\u4ece\u6307\u5b9a\u7684\u4f4d\u7f6e\u5f00\u59cb\u67e5\u627e\uff0c\u7b2c\u4e00\u4e2a\u4f4d\u7f6e\u662f1.<\/p>\n\n\n\n
gbase> select instr('123123412345',1,1);\n+---------------------------+\n| instr('123123412345',1,1) |\n+---------------------------+\n| 1 |\n+---------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n\u4ece\u7b2c2\u4e2a\u4f4d\u7f6e\u5f00\u59cb\u67e5\u627e\uff0c\u8fd4\u56de\u7684\u662f\u5176\u540e\u9762\u7684\u7b2c\u4e00\u6b21\u51fa\u73b0\u4f4d\u7f6e\u3002<\/p>\n\n\n\n
gbase> select instr('123123412345',1,2);\n+---------------------------+\n| instr('123123412345',1,2) |\n+---------------------------+\n| 4 |\n+---------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u6307\u5b9a\u8d77\u59cb\u4f4d\u7f6e0<\/span><\/h3>\n\n\n\n\u8fd4\u56de0<\/p>\n\n\n\n
gbase> select instr('123123412345',1,0);\n+---------------------------+\n| instr('123123412345',1,0) |\n+---------------------------+\n| 0 |\n+---------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u6307\u5b9a\u51fa\u73b0\u7684\u6b21\u6570<\/span><\/h3>\n\n\n\n\u5982\u4e0b\u5206\u522b\u67e5\u627e\u7b2c1\uff0c2\uff0c3\u6b21\u51fa\u73b0\u7684\u4f4d\u7f6e\u3002\u4e3a\u65b9\u4fbf\u5bf9\u6bd4\uff0c\u8d77\u59cb\u4f4d\u7f6e\u7528\u7684\u90fd\u662f1\u3002<\/p>\n\n\n\n
gbase> select instr('123123412345',1,1,1);\n+-----------------------------+\n| instr('123123412345',1,1,1) |\n+-----------------------------+\n| 1 |\n+-----------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('123123412345',1,1,2);\n+-----------------------------+\n| instr('123123412345',1,1,2) |\n+-----------------------------+\n| 4 |\n+-----------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('123123412345',1,1,3);\n+-----------------------------+\n| instr('123123412345',1,1,3) |\n+-----------------------------+\n| 8 |\n+-----------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>\n\n\n\n<\/span>\u53cd\u5411\u67e5\u627e<\/span><\/h3>\n\n\n\n\u548c\u524d\u4e00\u4e2a\u4f8b\u5b50\u53c2\u6570\u76f8\u540c\uff0c\u53ea\u4e0d\u8fc7\u8d77\u59cb\u4f4d\u7f6e\u662f-1\u3002 \u5176\u7ed3\u679c\u4e5f\u662f\u6b63\u597d\u53cd\u8fc7\u6765\u5339\u914d\u5230\u7684\u4f4d\u7f6e\u3002<\/p>\n\n\n\n
gbase> select instr('123123412345',1,-1,1);\n+------------------------------+\n| instr('123123412345',1,-1,1) |\n+------------------------------+\n| 8 |\n+------------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('123123412345',1,-1,2);\n+------------------------------+\n| instr('123123412345',1,-1,2) |\n+------------------------------+\n| 4 |\n+------------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('123123412345',1,-1,3);\n+------------------------------+\n| instr('123123412345',1,-1,3) |\n+------------------------------+\n| 1 |\n+------------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n\ngbase> select instr('123123412345',1,-1,4);\n+------------------------------+\n| instr('123123412345',1,-1,4) |\n+------------------------------+\n| 0 |\n+------------------------------+\n1 row in set (Elapsed: 00:00:00.00)\n<\/code><\/pre>","protected":false},"excerpt":{"rendered":"\u672c\u6587\u4ecb\u7ecdGBase 8a\u5185\u7f6e\u7684INSTR\u51fd\u6570\u4f7f\u7528\u65b9\u6cd5\u548c\u6837\u4f8b\u3002\u8be5\u51fd\u6570\u7528\u4e8e\u5728\u6307\u5b9a\u5b57\u7b26\u4e32\u91cc\u67e5\u627e\u76ee\u6807\u5b57\u7b26\u4e32\u51fa\u73b0\u7684\u4f4d\u7f6e\u3002<\/p>","protected":false},"author":1,"featured_media":0,"comment_status":"closed","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[3],"tags":[36],"class_list":["post-6457","post","type-post","status-publish","format-standard","hentry","category-gbase8a","tag-36"],"_links":{"self":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6457","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/comments?post=6457"}],"version-history":[{"count":12,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6457\/revisions"}],"predecessor-version":[{"id":6477,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/posts\/6457\/revisions\/6477"}],"wp:attachment":[{"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/media?parent=6457"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/categories?post=6457"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.gbase8.cn\/en\/wp-json\/wp\/v2\/tags?post=6457"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}