{"id":355,"date":"2023-09-16T10:44:52","date_gmt":"2023-09-16T02:44:52","guid":{"rendered":""},"modified":"2023-09-18T11:50:02","modified_gmt":"2023-09-18T03:50:02","slug":"sql%e4%b8%ad%e5%ad%97%e7%ac%a6%e4%b8%b2%e6%88%aa%e5%8f%96%e4%b8%8e%e6%8b%bc%e6%8e%a5","status":"publish","type":"post","link":"https:\/\/mushiming.com\/355.html","title":{"rendered":"sql\u4e2d\u5b57\u7b26\u4e32\u622a\u53d6\u4e0e\u62fc\u63a5."},"content":{"rendered":"<p><svg xmlns=\"http:\/\/www.w3.org\/2000\/svg\" style=\"display: none;\"> \n <path stroke-linecap=\"round\" d=\"M5,0 0,2.5 5,5z\" id=\"raphael-marker-block\" style=\"-webkit-tap-highlight-color: rgba(0, 0, 0, 0);\"><\/path> \n<\/svg> <\/p>\n<p><strong>\u4e00. <strong>\u622a\u53d6<\/strong>:<\/strong><\/p>\n<pre><code>1**.RIGHT(str,length)**\u65b9\u6cd5:\u4ece\u6700\u53f3\u8fb9\u5f00\u59cb\u622a\u53d6\n\t\u53c2\u6570:      str:    \u8981\u622a\u53d6\u7684\u5b57\u7b26\u4e32\tlength: \t\u8981\u622a\u53d6\u7684\u957f\u5ea6\n\t\u5b9e\u4f8b:SELECT RIGHT('hello Ron!',4)  ----&gt; \"Ron!\"\n\t\n2**.LEFT(str,length)**\u65b9\u6cd5:\u4ece\u6700\u5de6\u8fb9\u5f00\u59cb\u622a\u53d6\n\t\u53c2\u6570:      str:    \u8981\u622a\u53d6\u7684\u5b57\u7b26\u4e32\tlength: \t\u8981\u622a\u53d6\u7684\u957f\u5ea6\n\t\u5b9e\u4f8b:SELECT LEFT('hello Ron!',4)  ----&gt; \"hell!\"\n\t\n3**.SUBSTRING(str,limit,length)**\u65b9\u6cd5:\u4ece\u6307\u5b9a\u4f4d\u7f6e\u5f00\u59cb\u622a\u53d6\n\t\u53c2\u6570:      str: \u8981\u622a\u53d6\u7684\u5b57\u7b26\u4e32\t\n\t\t\t\tlimit:\t\u622a\u53d6\u5f00\u59cb\u7684\u4f4d\u7f6e\t(\u6ce8\u610f:\u4e0b\u8868\u4ece1\u5f00\u59cb)\n\t\t\t\tlength: \u8981\u622a\u53d6\u7684\u957f\u5ea6\n\t\u5b9e\u4f8b:SELECT SUBSTRING('hello Ron!',1 ,2) ----&gt; \"he!\" \n<\/code><\/pre>\n<p>\u4e8c. <strong>\u62fc\u63a5<\/strong>:<\/p>\n<pre><code>1**.CONCAT(str1,str2,...)**\u65b9\u6cd5:\n\t\u53c2\u6570: str : \u8981\u62fc\u63a5\u7684\u5b57\u7b26\u4e32\n\t\u5b9e\u4f8b:SELECT CONCAT('11','22','33') ----&gt;  \"112233\"\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"\u4e00.\u622a\u53d6:1**.RIGHT(str,length)**\u65b9\u6cd5:\u4ece\u6700\u53f3\u8fb9\u5f00\u59cb\u622a\u53d6\t\u53c2\u6570:str:\u8981\u622a\u53d6\u7684\u5b57\u7b26\u4e32\tlength:\t\u8981\u622a\u53d6\u7684\u957f\u5ea6\t\u5b9e\u4f8b:SELECTRIGHT('h...","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[82],"tags":[],"_links":{"self":[{"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/posts\/355"}],"collection":[{"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/comments?post=355"}],"version-history":[{"count":0,"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/posts\/355\/revisions"}],"wp:attachment":[{"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/media?parent=355"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/categories?post=355"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mushiming.com\/wp-json\/wp\/v2\/tags?post=355"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}