PHP mysql基本语句指令
1 /* 选择数据库 2 use test; 3 */ 4 5 /* 显示所有的数据库 6 show databases; 7 */ 8 9 /* 删除表/数据库 10 drop database test1; 11 delete from user1 where id=4; 12 */ 13 14 /* 创建表 15 CREATE TABLE user1( 16 id int primary key auto_increment
<span> 1</span> <span>/*</span><span>选择数据库 </span><span> 2</span> <span> use test; </span><span> 3</span> <span>*/</span> <span> 4</span> <span> 5</span> <span>/*</span><span> 显示所有的数据库 </span><span> 6</span> <span> show databases; </span><span> 7</span> <span>*/</span> <span> 8</span> <span> 9</span> <span>/*</span><span>删除表/数据库 </span><span>10</span> <span> drop database test1; </span><span>11</span> <span> delete from user1 where id=4; </span><span>12</span> <span>*/</span> <span>13</span> <span>14</span> <span>/*</span><span>创建表 </span><span>15</span> <span> CREATE TABLE user1( </span><span>16</span> <span>id int primary key auto_increment, </span><span>17</span> <span>name varchar(32) not null, </span><span>18</span> <span>password varchar(64) not null, </span><span>19</span> <span>email varchar(128) not null, </span><span>20</span> <span>age tinyint unsigned not null);</span><span>*/</span> <span>21</span> <span>22</span> <span>/*</span><span>插入数据 </span><span>23</span> <span> insert into user1(name,password,email,age) </span><span>24</span> <span> values('daomul',md5('daomul'),'975052664@qq.com','22'); </span><span>25</span> <span>*/</span> <span>26</span> <span>27</span> <span>/*</span><span>查询数据 </span><span>28</span> <span> select * from user1; </span><span>29</span> <span>*/</span> <span>30</span> <span>31</span> <span>/*</span><span>输入中文的问题解决 </span><span>32</span> <span> set character_set_client-gbk; </span><span>33</span> <span> set character_set_result-gbk; </span><span>34</span> <span>35</span> <span> #显示所有字符类型 :show variables like '%char%'; </span><span>36</span> <span>37</span> <span>*/</span>
1、查询一行数据
"select name from user1 where age=' " .$age. " ' limit 0,1;" //控制在0-1条数据
2、模糊查询
"select name from user1 where email like ' % " $email " %' ";
3、批量执行 sql语句
3.1 批量执行dml语句
(1 $sql="$sql1;$sql; ....";
或者 :$sqls="" ; $sqls.=""; $sqls.=""; ....
(2 mysqli::multi_query($sqls); //执行操作,并返回 操作的数目。
3.2 批量执行dml语句
具体事例:见 http://www.cnblogs.com/daomul/p/3381782.html
4、自我复制:测试高度的数据
insert into emp(name,grade,email,school,salary,remark)select name,grade,email,school,salary,remark from emp;

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