Question

以下是我的查询，大约1分钟需要一些时间，有时会在一秒内给出结果，特别是我在一段时间之后执行查询，或者在查询中添加了一些新关键字。看起来像是一些索引问题，当我执行执行计划时，RID查找成本为60％。源表有大约2-5个Lacs数据，每天大约10,000-20,000行将被添加。请建议我。感谢

SELECT *
FROM   (SELECT Row_number() OVER (ORDER BY rank DESC, jobid DESC) AS rnum,
               *
        FROM   (SELECT rank,
                       joblistview.*
                FROM   joblistview,
                       FREETEXTTABLE(joblistview, jobtitle, 'seo manager') f
                WHERE  joblistview.jobid = f.[key]
                       AND CONTAINS(joblistview.joblocation, 'mumbai')
                UNION
                SELECT rank,
                       joblistview.*
                FROM   joblistview,
                       FREETEXTTABLE(joblistview, jobdescription, 'seo manager')
                       f
                WHERE  joblistview.jobid = f.[key]
                       AND CONTAINS(joblistview.joblocation, 'mumbai')
                UNION
                SELECT rank,
                       joblistview.*
                FROM   joblistview,
                       FREETEXTTABLE(joblistview, company_name, 'seo manager') f
                WHERE  joblistview.jobid = f.[key]
                       AND CONTAINS(joblistview.joblocation, 'mumbai')) AS xx)AS
       tt
WHERE  rnum BETWEEN 11 AND 20

执行计划

SQL Execution Plan

Answer 1

您可以在单个FREETEXTTABLE搜索中指定多个列，这样就不需要使用UNION进行多次查询。

SELECT *
FROM   (SELECT Row_number() OVER (ORDER BY rank DESC, jobid DESC) AS rnum,
               *
        FROM   (SELECT rank,
                       joblistview.*
                FROM   joblistview,
                       FREETEXTTABLE(joblistview, (jobtitle,jobdescription,company_name), 'seo manager') f
                WHERE  joblistview.jobid = f.[key]
                       AND CONTAINS(joblistview.joblocation, 'mumbai')
               ) AS xx
       ) AS tt
WHERE  rnum BETWEEN 11 AND 20

Answer 2

您是否尝试添加包含所有搜索列数据的计算列？然后将此计算列配置为持久化并使其成为全文索引。然后你可以尝试

SELECT *
FROM   (SELECT Row_number() OVER (ORDER BY rank DESC, jobid DESC) AS rnum,
               *
        FROM   (SELECT rank,
                       joblistview.*
                FROM   joblistview,
                       FREETEXTTABLE(joblistview, (<<<ComputedColumn>>>), 'seo manager') f
                WHERE  joblistview.jobid = f.[key]
                       AND CONTAINS(joblistview.joblocation, 'mumbai')
               ) AS xx
       ) AS tt
WHERE  rnum BETWEEN 11 AND 20

SQL Server查询一段时间用freetexttable花费太多时间 - 看起来索引问题

2 个答案: