在帝国CMS中,通过SQL语句查询特定栏目的数据是一项常见操作,本文将详细介绍如何在帝国CMS中使用SQL进行栏目查询,包括具体步骤、示例代码和常见问题的解答。
一、基本概念与背景
帝国CMS是一款功能强大的内容管理系统,广泛应用于各类网站开发中,在进行数据操作时,经常需要使用SQL语句来查询特定的栏目信息,如一级栏目、二级栏目等,这些查询可以帮助管理员更好地管理和展示网站内容。
二、SQL查询方法
1. 查询指定栏目ID下的所有TAG
方法1:
select DISTINCT([!db.pre!]enewstags.tagname), [!db.pre!]enewstags.tagid, [!db.pre!]enewstags.num from [!db.pre!]enewstags inner join [!db.pre!]enewstagsdata on [!db.pre!]enewstags.tagid = [!db.pre!]enewstagsdata.tagid where [!db.pre!]enewstagsdata.classid = 34 order by [!db.pre!]enewstags.num DESC limit 30
模板代码:
[e:loop={"select DISTINCT([!db.pre!]enewstags.tagname), [!db.pre!]enewstags.tagid, [!db.pre!]enewstags.num from [!db.pre!]enewstags inner join [!db.pre!]enewstagsdata on [!db.pre!]enewstags.tagid = [!db.pre!]enewstagsdata.tagid where [!db.pre!]enewstagsdata.classid = 34 order by [!db.pre!]enewstags.num DESC limit 30", 0, 24}] <a href='<?>个'</a>[/e:loop]
此方法使用DISTINCT
关键字去除重复项,并按标签数量降序排列,限制返回30条记录。
方法2:
select a.tagname, a.num, b.tagid from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by tagid order by num desc limit 40
模板代码:
[e:loop={"select a.tagname, a.num, b.tagid from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by tagid order by num desc limit 40", 40, 24, 0}] <a href='<?>个'<?> (<?>) </a>[/e:loop]
此方法通过分组和排序获取指定栏目下的标签,限制返回40条记录。
方法3:
select a.*, b.* from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by b.tagid order by a.num desc limit 40
模板代码:
[e:loop={"select a.*, b.* from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by b.tagid order by a.num desc limit 40", 40, 24, 0}] <a href='<?>个'<?>)</a>[/e:loop]
此方法选择所有字段,按标签数量降序排列,限制返回40条记录。
方法4:
select a.*, b.* from [!db.pre!]enewstags a LEFT JOIN [!db.pre!]enewstagsdata b ON a.tagid = b.tagid where classid = 34 group by b.tagid order by a.num desc limit 100
模板代码:
[e:loop={"select a.*, b.* from [!db.pre!]enewstags a LEFT JOIN [!db.pre!]enewstagsdata b ON a.tagid = b.tagid where classid = 34 group by b.tagid order by a.num desc limit 100", 0, 24, 0}] <a href='<?>个'<?>)</a>[/e:loop]
此方法使用左连接,按标签数量降序排列,限制返回100条记录。
2. 调用单个或多个栏目
单个栏目:
将classid = 34
替换为所需栏目的ID,要查询栏目ID为1的信息,可以将SQL中的classid = 34
替换为classid = 1
。
多个栏目:
将classid = 34
替换为classid in(34, 35, 36, 37)
,可以一次查询多个栏目的信息。
select * from [!db.pre!]enewsclass where classid in(34, 35, 36, 37)
当前栏目:
将classid = 34
替换为classid = '$GLOBALS[navclassid]'
,可以动态获取当前栏目的信息。
$bclassid=$GLOBALS[navclassid]; //取得本栏目id
然后使用该变量构建SQL语句:
select * from [!db.pre!]enewsclass where bclassid='$bclassid' order by classid desc
3. 获取一级、二级和三级栏目信息
一级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=0 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
二级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=1 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
三级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=2 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
SQL语句分别用于查询一级、二级和三级栏目的信息,其中bclassid
表示上级栏目ID,ishidden
和ischeck
用于过滤隐藏和未审核的栏目。
三、相关问题与解答
Q1: 如何在帝国CMS中通过SQL查询指定栏目下的所有TAG?
A1: 可以通过以下四种方法实现:
1、方法1:
select DISTINCT([!db.pre!]enewstags.tagname), [!db.pre!]enewstags.tagid, [!db.pre!]enewstags.num from [!db.pre!]enewstags inner join [!db.pre!]enewstagsdata on [!db.pre!]enewstags.tagid = [!db.pre!]enewstagsdata.tagid where [!db.pre!]enewstagsdata.classid = 34 order by [!db.pre!]enewstags.num DESC limit 30
2、方法2:
select a.tagname, a.num, b.tagid from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by tagid order by num desc limit 40
3、方法3:
select a.*, b.* from [!db.pre!]enewstags a, [!db.pre!]enewstagsdata b where a.tagid = b.tagid and classid = 34 group by b.tagid order by a.num desc limit 40
4、方法4:
select a.*, b.* from [!db.pre!]enewstags a LEFT JOIN [!db.pre!]enewstagsdata b ON a.tagid = b.tagid where classid = 34 group by b.tagid order by a.num desc limit 100
将上述SQL语句中的classid = 34
替换为所需的栏目ID即可。
Q2: 如何在帝国CMS中通过SQL查询一级、二级和三级栏目信息?
A2: 可以通过以下SQL语句分别查询一级、二级和三级栏目信息:
1、一级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=0 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
2、二级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=1 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
3、三级栏目:
SELECT classid, classname, classpath, wburl, islast FROM {$dbtbpre}enewsclass WHERE bclassid=2 AND ishidden = 0 AND ischeck = 0 ORDER BY myorder ASC
这些SQL语句通过设置不同的bclassid
值来筛选不同级别的栏目信息,并通过ishidden
和ischeck
字段过滤隐藏和未审核的栏目。
来源互联网整合,作者:小编,如若转载,请注明出处:https://www.aiboce.com/ask/119629.html