{"id":197,"date":"2021-08-10T15:50:03","date_gmt":"2021-08-10T07:50:03","guid":{"rendered":"https:\/\/9iwd.top\/?p=197"},"modified":"2021-08-10T15:50:04","modified_gmt":"2021-08-10T07:50:04","slug":"no5-mysql-%e6%9d%a1%e4%bb%b6%e6%9f%a5%e8%af%a2","status":"publish","type":"post","link":"http:\/\/9iwd.top\/?p=197","title":{"rendered":"No5 mysql \u6761\u4ef6\u67e5\u8be2"},"content":{"rendered":"\n<pre class=\"wp-block-code\"><code>\u4ec0\u4e48\u662f\u6761\u4ef6\u67e5\u8be2\uff1f\n\t\u4e0d\u662f\u5c06\u8868\u4e2d\u6240\u6709\u6570\u636e\u90fd\u67e5\u51fa\u6765\u3002\u662f\u67e5\u8be2\u51fa\u6765\u7b26\u5408\u6761\u4ef6\u7684\u3002\n\t\u8bed\u6cd5\u683c\u5f0f\uff1a\n\t\tselect\n\t\t\t\u5b57\u6bb51,\u5b57\u6bb52,\u5b57\u6bb53....\n\t\tfrom \n\t\t\t\u8868\u540d\n\t\twhere\n\t\t\t\u6761\u4ef6;\n\u90fd\u6709\u54ea\u4e9b\u6761\u4ef6\uff1f\n\u7b49\u4e8e : =\r\n\u4e0d\u7b49\u4e8e : &lt;> \u6216 !=\r\n\u5c0f\u4e8e : &lt;\r\n\u5927\u4e8e : >\r\n\u5c0f\u4e8e\u7b49\u4e8e : &lt;=\r\n\u5927\u4e8e\u7b49\u4e8e : >=\r\n\u4e24\u503c\u4e4b\u95f4 : between\r\n\u7a7a\u503c : null\r\n\u4e0d\u4e3a\u7a7a\u503c : is not null\n\u5e76\u4e14 : and\r\n\u6216\u8005 : or\r\n\u5305\u542b : in\r\n\u53d6\u975e : not\r\n\u6a21\u7cca\u67e5\u8be2 : like\r\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u7b49\u4e8e : =\n\/\/\u67e5\u8be2\u85aa\u8d44\u7b49\u4e8e800\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename from emp where sal = 800;\r\n+-------+-------+\r\n| empno | ename |\r\n+-------+-------+\r\n|  7369 | SMITH |\r\n+-------+-------+\n\n\/\/\u67e5\u8be2SMITH\u7684\u7f16\u53f7\u548c\u85aa\u8d44\uff1f\n\/\/\/\/\u5b57\u7b26\u4e32\u4f7f\u7528\u5355\u5f15\u53f7\nmysql> select empno,sal from emp where ename = 'SMITH';\r\n+-------+--------+\r\n| empno | sal    |\r\n+-------+--------+\r\n|  7369 | 800.00 |\r\n+-------+--------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u4e0d\u7b49\u4e8e : &lt;> \u6216 !=\n\/\/\u67e5\u8be2\u85aa\u8d44\u4e0d\u7b49\u4e8e800\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename from emp where sal != 800;\r\n+-------+--------+\r\n| empno | ename  |\r\n+-------+--------+\r\n|  7499 | ALLEN  |\r\n|  7521 | WARD   |\r\n|  7566 | JONES  |\r\n|  7654 | MARTIN |\r\n|  7698 | BLAKE  |\r\n|  7782 | CLARK  |\r\n|  7788 | SCOTT  |\r\n|  7839 | KING   |\r\n|  7844 | TURNER |\r\n|  7876 | ADAMS  |\r\n|  7900 | JAMES  |\r\n|  7902 | FORD   |\r\n|  7934 | MILLER |\r\n+-------+--------+\n\nmysql> select empno,ename from emp where sal &lt;> 800;\r\n+-------+--------+\r\n| empno | ename  |\r\n+-------+--------+\r\n|  7499 | ALLEN  |\r\n|  7521 | WARD   |\r\n|  7566 | JONES  |\r\n|  7654 | MARTIN |\r\n|  7698 | BLAKE  |\r\n|  7782 | CLARK  |\r\n|  7788 | SCOTT  |\r\n|  7839 | KING   |\r\n|  7844 | TURNER |\r\n|  7876 | ADAMS  |\r\n|  7900 | JAMES  |\r\n|  7902 | FORD   |\r\n|  7934 | MILLER |\r\n+-------+--------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5c0f\u4e8e : &lt;\r\n\/\/\u67e5\u8be2\u85aa\u8d44\u5c0f\u4e8e2000\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename,sal from emp where sal &lt; 2000;\r\n+-------+--------+---------+\r\n| empno | ename  | sal     |\r\n+-------+--------+---------+\r\n|  7369 | SMITH  |  800.00 |\r\n|  7499 | ALLEN  | 1600.00 |\r\n|  7521 | WARD   | 1250.00 |\r\n|  7654 | MARTIN | 1250.00 |\r\n|  7844 | TURNER | 1500.00 |\r\n|  7876 | ADAMS  | 1100.00 |\r\n|  7900 | JAMES  |  950.00 |\r\n|  7934 | MILLER | 1300.00 |\r\n+-------+--------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5c0f\u4e8e\u7b49\u4e8e : &lt;=\r\n\/\/\u67e5\u8be2\u85aa\u8d44\u5c0f\u4e8e\u7b49\u4e8e3000\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename,sal from emp where sal &lt;= 3000;\r\n+-------+--------+---------+\r\n| empno | ename  | sal     |\r\n+-------+--------+---------+\r\n|  7369 | SMITH  |  800.00 |\r\n|  7499 | ALLEN  | 1600.00 |\r\n|  7521 | WARD   | 1250.00 |\r\n|  7566 | JONES  | 2975.00 |\r\n|  7654 | MARTIN | 1250.00 |\r\n|  7698 | BLAKE  | 2850.00 |\r\n|  7782 | CLARK  | 2450.00 |\r\n|  7788 | SCOTT  | 3000.00 |\r\n|  7844 | TURNER | 1500.00 |\r\n|  7876 | ADAMS  | 1100.00 |\r\n|  7900 | JAMES  |  950.00 |\r\n|  7902 | FORD   | 3000.00 |\r\n|  7934 | MILLER | 1300.00 |\r\n+-------+--------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5927\u4e8e : >\r\n\/\/\u67e5\u8be2\u85aa\u8d44\u5927\u4e8e3000\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename,sal from emp where sal > 3000;\r\n+-------+-------+---------+\r\n| empno | ename | sal     |\r\n+-------+-------+---------+\r\n|  7839 | KING  | 5000.00 |\r\n+-------+-------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5927\u4e8e\u7b49\u4e8e : >=\r\n\/\/\u67e5\u8be2\u85aa\u8d44\u5927\u4e8e\u7b49\u4e8e3000\u7684\u5458\u5de5\u59d3\u540d\u548c\u7f16\u53f7\uff1f\nmysql> select empno,ename,sal from emp where sal >= 3000;\r\n+-------+-------+---------+\r\n| empno | ename | sal     |\r\n+-------+-------+---------+\r\n|  7788 | SCOTT | 3000.00 |\r\n|  7839 | KING  | 5000.00 |\r\n|  7902 | FORD  | 3000.00 |\r\n+-------+-------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u4e24\u503c\u4e4b\u95f4 : between\r\n\/\/between \u2026 and \u2026. \u4e24\u4e2a\u503c\u4e4b\u95f4, \u7b49\u540c\u4e8e >= and &lt;=\n\/\/\u67e5\u8be2\u85aa\u8d44\u57282450\u548c3000\u4e4b\u95f4\u7684\u5458\u5de5\u4fe1\u606f\uff1f\u5305\u62ec2450\u548c3000\n\/\/\u7b2c\u4e00\u79cd\u65b9\u5f0f\uff1a>= and &lt;= \uff08and\u662f\u5e76\u4e14\u7684\u610f\u601d\u3002\uff09\nmysql> select empno,ename,sal from emp where sal >= 2450 and sal &lt;= 3000;\r\n+-------+-------+---------+\r\n| empno | ename | sal     |\r\n+-------+-------+---------+\r\n|  7566 | JONES | 2975.00 |\r\n|  7698 | BLAKE | 2850.00 |\r\n|  7782 | CLARK | 2450.00 |\r\n|  7788 | SCOTT | 3000.00 |\r\n|  7902 | FORD  | 3000.00 |\r\n+-------+-------+---------+\n\n\/\/\u7b2c\u4e8c\u79cd\u65b9\u5f0f\uff1abetween \u2026 and \u2026\n\/*\nselect \r\n\tempno,ename,sal \r\nfrom \r\n\temp \r\nwhere \r\n\tsal between 2450 and 3000;\r\n\t\t\t\r\n\u6ce8\u610f\uff1a\r\n\t\u4f7f\u7528between and\u7684\u65f6\u5019\uff0c\u5fc5\u987b\u9075\u5faa\u5de6\u5c0f\u53f3\u5927\u3002\r\n\tbetween and\u662f\u95ed\u533a\u95f4\uff0c\u5305\u62ec\u4e24\u7aef\u7684\u503c\u3002\n*\/\nmysql> select empno,ename,sal from emp where sal between 2450 and 3000;\r\n+-------+-------+---------+\r\n| empno | ename | sal     |\r\n+-------+-------+---------+\r\n|  7566 | JONES | 2975.00 |\r\n|  7698 | BLAKE | 2850.00 |\r\n|  7782 | CLARK | 2450.00 |\r\n|  7788 | SCOTT | 3000.00 |\r\n|  7902 | FORD  | 3000.00 |\r\n+-------+-------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u7a7a\u503c : null\r\n\/\/\u67e5\u8be2\u54ea\u4e9b\u5458\u5de5\u7684\u6d25\u8d34\/\u8865\u52a9\u4e3anull\uff1f\nmysql>  select empno,ename,sal,comm from emp where comm = null;\r\nEmpty set (0.00 sec)\n\nmysql> select empno,ename,sal,comm from emp where comm is null;\r\n+-------+--------+---------+------+\r\n| empno | ename  | sal     | comm |\r\n+-------+--------+---------+------+\r\n|  7369 | SMITH  |  800.00 | NULL |\r\n|  7566 | JONES  | 2975.00 | NULL |\r\n|  7698 | BLAKE  | 2850.00 | NULL |\r\n|  7782 | CLARK  | 2450.00 | NULL |\r\n|  7788 | SCOTT  | 3000.00 | NULL |\r\n|  7839 | KING   | 5000.00 | NULL |\r\n|  7876 | ADAMS  | 1100.00 | NULL |\r\n|  7900 | JAMES  |  950.00 | NULL |\r\n|  7902 | FORD   | 3000.00 | NULL |\r\n|  7934 | MILLER | 1300.00 | NULL |\r\n+-------+--------+---------+------+\n\n\/*\n\u6ce8\u610f\uff1a\u5728\u6570\u636e\u5e93\u5f53\u4e2dnull\u4e0d\u80fd\u4f7f\u7528\u7b49\u53f7\u8fdb\u884c\u8861\u91cf\u3002\u9700\u8981\u4f7f\u7528is null\r\n\u56e0\u4e3a\u6570\u636e\u5e93\u4e2d\u7684null\u4ee3\u8868\u4ec0\u4e48\u4e5f\u6ca1\u6709\uff0c\u5b83\u4e0d\u662f\u4e00\u4e2a\u503c\uff0c\u6240\u4ee5\u4e0d\u80fd\u4f7f\u7528\r\n\u7b49\u53f7\u8861\u91cf\n*\/\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u4e0d\u4e3a\u7a7a\u503c: is not null\r\n\/\/\u67e5\u8be2\u54ea\u4e9b\u5458\u5de5\u7684\u6d25\u8d34\/\u8865\u52a9\u4e0d\u4e3anull\uff1f\r\nmysql> select empno,ename,sal,comm from emp where comm is not null;\r\n+-------+--------+---------+---------+\r\n| empno | ename  | sal     | comm    |\r\n+-------+--------+---------+---------+\r\n|  7499 | ALLEN  | 1600.00 |  300.00 |\r\n|  7521 | WARD   | 1250.00 |  500.00 |\r\n|  7654 | MARTIN | 1250.00 | 1400.00 |\r\n|  7844 | TURNER | 1500.00 |    0.00 |\r\n+-------+--------+---------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5e76\u4e14 : and\r\n\/\/\u67e5\u8be2\u5de5\u4f5c\u5c97\u4f4d\u662fMANAGER\u5e76\u4e14\u5de5\u8d44\u5927\u4e8e2500\u7684\u5458\u5de5\u4fe1\u606f\uff1f\nselect \r\n\tempno,ename,job,sal \r\nfrom \r\n\temp \r\nwhere \r\n\tjob = 'MANAGER' and sal > 2500;\nmysql> select\r\n    -> empno,ename,job,sal\r\n    -> from\r\n    -> emp\r\n    -> where\r\n    -> job = 'MANAGER' and sal > 2500;\r\n+-------+-------+---------+---------+\r\n| empno | ename | job     | sal     |\r\n+-------+-------+---------+---------+\r\n|  7566 | JONES | MANAGER | 2975.00 |\r\n|  7698 | BLAKE | MANAGER | 2850.00 |\r\n+-------+-------+---------+---------+\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u6216\u8005 : or\r\n\/\/\u67e5\u8be2\u5de5\u4f5c\u5c97\u4f4d\u662fMANAGER\u548cSALESMAN\u7684\u5458\u5de5\uff1f\nselect \r\n\tempno,ename,job\r\nfrom\r\n\temp\r\nwhere \r\n\tjob = 'MANAGER' or job = 'SALESMAN';\n\nmysql> select\r\n    -> empno,ename,job\r\n    -> from\r\n    -> emp\r\n    -> where\r\n    -> job = 'MANAGER' or job = 'SALESMAN';\r\n+-------+--------+----------+\r\n| empno | ename  | job      |\r\n+-------+--------+----------+\r\n|  7499 | ALLEN  | SALESMAN |\r\n|  7521 | WARD   | SALESMAN |\r\n|  7566 | JONES  | MANAGER  |\r\n|  7654 | MARTIN | SALESMAN |\r\n|  7698 | BLAKE  | MANAGER  |\r\n|  7782 | CLARK  | MANAGER  |\r\n|  7844 | TURNER | SALESMAN |\r\n+-------+--------+----------+\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/and\u548cor\u540c\u65f6\u51fa\u73b0\u7684\u8bdd\uff0c\u6709\u4f18\u5148\u7ea7\u95ee\u9898\u5417\uff1f\r\n\/\/\u67e5\u8be2\u5de5\u8d44\u5927\u4e8e2500\uff0c\u5e76\u4e14\u90e8\u95e8\u7f16\u53f7\u4e3a10\u621620\u90e8\u95e8\u7684\u5458\u5de5\uff1f\n\/*\nselect \r\n\t*\r\nfrom\r\n\temp\r\nwhere\r\n\tsal > 2500 and deptno = 10 or deptno = 20;\n\u5206\u6790\u4ee5\u4e0a\u8bed\u53e5\u7684\u95ee\u9898\uff1f\r\n\tand\u4f18\u5148\u7ea7\u6bd4or\u9ad8\u3002\r\n\t\u4ee5\u4e0a\u8bed\u53e5\u4f1a\u5148\u6267\u884cand\uff0c\u7136\u540e\u6267\u884cor\u3002\r\n\t\u4ee5\u4e0a\u8fd9\u4e2a\u8bed\u53e5\u8868\u793a\u4ec0\u4e48\u542b\u4e49\uff1f\r\n\t\u627e\u51fa\u5de5\u8d44\u5927\u4e8e2500\u5e76\u4e14\u90e8\u95e8\u7f16\u53f7\u4e3a10\u7684\u5458\u5de5\uff0c\u6216\u800520\u90e8\u95e8\u6240\u6709\u5458\u5de5\u627e\u51fa\u6765\u3002\n\nselect \r\n\t*\r\nfrom\r\n\temp\r\nwhere\r\n\tsal > 2500 and (deptno = 10 or deptno = 20);\r\n\t\t\r\nand\u548cor\u540c\u65f6\u51fa\u73b0\uff0cand\u4f18\u5148\u7ea7\u8f83\u9ad8\u3002\u5982\u679c\u60f3\u8ba9or\u5148\u6267\u884c\uff0c\u9700\u8981\u52a0\u201c\u5c0f\u62ec\u53f7\u201d\r\n\u4ee5\u540e\u5728\u5f00\u53d1\u4e2d\uff0c\u5982\u679c\u4e0d\u786e\u5b9a\u4f18\u5148\u7ea7\uff0c\u5c31\u52a0\u5c0f\u62ec\u53f7\u5c31\u884c\u4e86\u3002\n*\/\n\nmysql> select\r\n    -> *\r\n    -> from\r\n    -> emp\r\n    -> where\r\n    -> sal > 2500 and (deptno = 10 or deptno = 20);\r\n+-------+-------+-----------+------+------------+---------+------+--------+\r\n| EMPNO | ENAME | JOB       | MGR  | HIREDATE   | SAL     | COMM | DEPTNO |\r\n+-------+-------+-----------+------+------------+---------+------+--------+\r\n|  7566 | JONES | MANAGER   | 7839 | 1981-04-02 | 2975.00 | NULL |     20 |\r\n|  7788 | SCOTT | ANALYST   | 7566 | 1987-04-19 | 3000.00 | NULL |     20 |\r\n|  7839 | KING  | PRESIDENT | NULL | 1981-11-17 | 5000.00 | NULL |     10 |\r\n|  7902 | FORD  | ANALYST   | 7566 | 1981-12-03 | 3000.00 | NULL |     20 |\r\n+-------+-------+-----------+------+------------+---------+------+--------+\r\n<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u5305\u542b : in\r\n\/\/\u76f8\u5f53\u4e8e\u591a\u4e2a or \uff08not in \u4e0d\u5728\u8fd9\u4e2a\u8303\u56f4\u4e2d\uff09\r\n\/\/\u67e5\u8be2\u5de5\u4f5c\u5c97\u4f4d\u662fMANAGER\u548cSALESMAN\u7684\u5458\u5de5\uff1f\n\/\/select empno,ename,job from emp where job = 'MANAGER' or job = 'SALESMAN';\r\n\/\/select empno,ename,job from emp where job in('MANAGER', 'SALESMAN');\n\nmysql> select empno,ename,job from emp where job in('MANAGER', 'SALESMAN');\r\n+-------+--------+----------+\r\n| empno | ename  | job      |\r\n+-------+--------+----------+\r\n|  7499 | ALLEN  | SALESMAN |\r\n|  7521 | WARD   | SALESMAN |\r\n|  7566 | JONES  | MANAGER  |\r\n|  7654 | MARTIN | SALESMAN |\r\n|  7698 | BLAKE  | MANAGER  |\r\n|  7782 | CLARK  | MANAGER  |\r\n|  7844 | TURNER | SALESMAN |\r\n+-------+--------+----------+\n\n\/\/\u67e5\u8be2\u85aa\u8d44\u662f800\u548c5000\u7684\u5458\u5de5\u4fe1\u606f\uff1f\n\/\/select ename,sal from emp where sal = 800 or sal = 5000;\r\n\/\/select ename,sal from emp where sal in(800, 5000); \/\/\u8fd9\u4e2a\u4e0d\u662f\u8868\u793a800\u52305000\u90fd\u627e\u51fa\u6765\u3002\n\nmysql> select ename,sal from emp where sal in(800, 5000);\r\n+-------+---------+\r\n| ename | sal     |\r\n+-------+---------+\r\n| SMITH |  800.00 |\r\n| KING  | 5000.00 |\r\n+-------+---------+\n\n\/\/ not in \u8868\u793a\u4e0d\u5728\u8fd9\u51e0\u4e2a\u503c\u5f53\u4e2d\u7684\u6570\u636e\n\/\/select ename,sal from emp where sal in(800, 5000, 3000);\n\/\/select ename,sal from emp where sal not in(800, 5000, 3000);\n\nmysql> select ename,sal from emp where sal not in(800, 5000, 3000);\r\n+--------+---------+\r\n| ename  | sal     |\r\n+--------+---------+\r\n| ALLEN  | 1600.00 |\r\n| WARD   | 1250.00 |\r\n| JONES  | 2975.00 |\r\n| MARTIN | 1250.00 |\r\n| BLAKE  | 2850.00 |\r\n| CLARK  | 2450.00 |\r\n| TURNER | 1500.00 |\r\n| ADAMS  | 1100.00 |\r\n| JAMES  |  950.00 |\r\n| MILLER | 1300.00 |\r\n+--------+---------+<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u53d6\u975e : not\r\n\/*\nnot \u53ef\u4ee5\u53d6\u975e\uff0c\u4e3b\u8981\u7528\u5728 is \u6216 in \u4e2d\r\nis null\r\nis not null\r\nin\r\nnot in\n\n\u4f7f\u7528\u65b9\u5f0f\u53ef\u4ee5\u5f80\u4e0a\u770b\u4e0a\u9762\u7684\u51e0\u4e2a\u4f8b\u5b50\n*\/<\/code><\/pre>\n\n\n\n<pre class=\"wp-block-code\"><code>\/\/\u6a21\u7cca\u67e5\u8be2 : like\r\n\/*\n\u79f0\u4e3a\u6a21\u7cca\u67e5\u8be2\uff0c\u652f\u6301%\u6216\u4e0b\u5212\u7ebf\u5339\u914d\r\n%\u5339\u914d\u4efb\u610f\u591a\u4e2a\u5b57\u7b26\r\n\u4e0b\u5212\u7ebf\uff1a\u4efb\u610f\u4e00\u4e2a\u5b57\u7b26\u3002\r\n\uff08%\u662f\u4e00\u4e2a\u7279\u6b8a\u7684\u7b26\u53f7\uff0c_ \u4e5f\u662f\u4e00\u4e2a\u7279\u6b8a\u7b26\u53f7\uff09\n*\/\n\n\/\/\u627e\u51fa\u540d\u5b57\u4e2d\u542b\u6709O\u7684\uff1f\nmysql>  select ename from emp where ename like '%O%';\r\n+-------+\r\n| ename |\r\n+-------+\r\n| JONES |\r\n| SCOTT |\r\n| FORD  |\r\n+-------+\n\n\/\/\u627e\u51fa\u540d\u5b57\u4ee5T\u7ed3\u5c3e\u7684\uff1f\r\nselect ename from emp where ename like '%T';\n\n\/\/\u627e\u51fa\u540d\u5b57\u4ee5K\u5f00\u59cb\u7684\uff1f\r\nselect ename from emp where ename like 'K%';\r\n\r\n\/\/\u627e\u51fa\u7b2c\u4e8c\u4e2a\u5b57\u6bcf\u662fA\u7684\uff1f\r\nselect ename from emp where ename like '_A%';\r\n\t\t\r\n\/\/\u627e\u51fa\u7b2c\u4e09\u4e2a\u5b57\u6bcd\u662fR\u7684\uff1f\r\nselect ename from emp where ename like '__R%';\n\n\/\/\u627e\u51fa\u540d\u5b57\u4e2d\u6709\u201c_\u201d\u7684\uff1f\nselect name from t_student where name like '%_%'; \/\/\u8fd9\u6837\u4e0d\u884c\u3002\nselect name from t_student where name like '%\\_%'; \/\/ \\\u8f6c\u4e49\u5b57\u7b26\u3002\n\n<\/code><\/pre>\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[11],"tags":[],"_links":{"self":[{"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/posts\/197"}],"collection":[{"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"http:\/\/9iwd.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=197"}],"version-history":[{"count":14,"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/posts\/197\/revisions"}],"predecessor-version":[{"id":211,"href":"http:\/\/9iwd.top\/index.php?rest_route=\/wp\/v2\/posts\/197\/revisions\/211"}],"wp:attachment":[{"href":"http:\/\/9iwd.top\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=197"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/9iwd.top\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=197"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/9iwd.top\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=197"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}