我想进行限制检查。主要 - 检查名称是否在最后3行。怎么做?Mysql检查限制3已经在db
$connect = db_connect();
$query = "SELECT * FROM `lastest` WHERE `name` LIKE '" .$name. "'";
$result = db_query($query, $connect);
if ($result) {
die('Already in db.'); }
我想进行限制检查。主要 - 检查名称是否在最后3行。怎么做?Mysql检查限制3已经在db
$connect = db_connect();
$query = "SELECT * FROM `lastest` WHERE `name` LIKE '" .$name. "'";
$result = db_query($query, $connect);
if ($result) {
die('Already in db.'); }
如果列ID是 “ID”:
谷歌搜索 “SQL得到最后一行”(不带引号),导致这个页面:
http://www.w3schools.com/sql/sql_func_last.asp
拿起你的数据库,并自定义请求以获取最后3行。然后写你在那里statment请求查询子请求(这一个谁得到最后3行)...
因此,假设您的主键为“ID”:
SELECT COUNT(*)
FROM
(SELECT id, name
FROM lastest
ORDER BY id DESC
LIMIT 3) sub_lastest
WHERE `name` LIKE [name];
检查is_exists列,这是我可以建议你:
is_exists = 1 =>名称存在
is_exists = 0 =>名称不存在
SELECT count(*) as is_exists,GROUP_CONCAT(`fname`) as a
FROM test.users
HAVING a LIKE "% YOUR_NAME %"
ORDER BY `fname` DESC
LIMIT 3 ;
尝试,让我知道,如果这是帮你
不要犹豫问任何问题
好运