sql声明结构如何在php中运行？

我是SQL和PHP的新手，执行SQL的方式如下：

$query  = 'SELECT session, id FROM AnalysePageview WHERE session="'.$sessionID.'"ORDER BY id DESC LIMIT 1';                 
$result = mysqli_query($link, $query);

    DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT ',' + QUOTENAME(description) 
                    from customerrewards
                    group by description, typeid
                    order by typeid
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT name,' + @cols + ' from 
             (
                select c.name,
                  cr.description,
                  r.typeid
                from customers c
                left join rewards r
                  on c.id = r.customerid
                left join customerrewards cr
                  on r.typeid = cr.typeid
            ) x
            pivot 
            (
                count(typeid)
                for description in (' + @cols + ')
            ) p '

execute(@query)

现在我在这个论坛上看到了这样的东西：

$query  = 'SELECT session, id FROM AnalysePageview WHERE session="'.$sessionID.'"ORDER BY id DESC LIMIT 1';                 
$result = mysqli_query($link, $query);

    DECLARE @cols AS NVARCHAR(MAX),
    @query  AS NVARCHAR(MAX)

select @cols = STUFF((SELECT ',' + QUOTENAME(description) 
                    from customerrewards
                    group by description, typeid
                    order by typeid
            FOR XML PATH(''), TYPE
            ).value('.', 'NVARCHAR(MAX)') 
        ,1,1,'')

set @query = 'SELECT name,' + @cols + ' from 
             (
                select c.name,
                  cr.description,
                  r.typeid
                from customers c
                left join rewards r
                  on c.id = r.customerid
                left join customerrewards cr
                  on r.typeid = cr.typeid
            ) x
            pivot 
            (
                count(typeid)
                for description in (' + @cols + ')
            ) p '

execute(@query)

如果我把它放在$query=DECLARE@cols中。。。我会得到一个错误

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如何在PHP中使用此声明？

恐怕无法运行此SQL

有关更多详细信息，请参阅：

仅允许在BEGIN中声明。。。结束复合语句 而且必须在开始时，在任何其他声明之前

---

这是否意味着没有使用mysqli_query的pivot表？似乎MySQL中的复杂语句只能在过程/函数中使用