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android - Android联系人数据库：如何高度优化手机查找表？

问题描述

当我想使用 phone_lookup 表查询 display_name 时，我发现介绍如下：

'表示查找电话号码结果的表格，例如来电显示。要执行查找，您必须将要查找的数字附加到 CONTENT_FILTER_URI。此查询在 android 开发人员中高度优化。

但我不知道谷歌是如何优化这个查询的？

https://developer.android.com/reference/android/provider/ContactsContract.PhoneLookup

我查询了一下，最后解释如下：

SELECT data1 AS number,
    contacts_view._id AS contact_id,
    contacts_view.photo_uri AS photo_uri,
       contacts_view.send_to_voicemail AS send_to_voicemail,
       data_id AS data_id,
       contacts_view.lookup AS lookup,
       contacts_view.display_name AS display_name,
       contacts_view.last_time_contacted AS last_time_contacted,
       contacts_view.has_phone_number AS has_phone_number,
       contacts_view.in_visible_group AS in_visible_group,
       contacts_view.photo_file_id AS photo_file_id,
       data3 AS label,
       contacts_view.starred AS starred,
       data4 AS normalized_number,
       contacts_view.photo_thumb_uri AS photo_thumb_uri,
       contacts_view.in_default_directory AS in_default_directory,
       contacts_view.photo_id AS photo_id,
       contacts_view.custom_ringtone AS custom_ringtone,
       contacts_view._id AS _id,
       data2 AS type,
       contacts_view.times_contacted AS times_contacted
  FROM raw_contacts
       JOIN
       view_contacts AS contacts_view ON (contacts_view._id = raw_contacts.contact_id),
       (
           SELECT data_id,
                  normalized_number,
                  length(normalized_number) AS len
             FROM phone_lookup
            WHERE (phone_lookup.min_match = '.....') 
       )
       AS lookup,
       data
 WHERE (lookup.data_id = data._id AND 
        data.raw_contact_id = raw_contacts._id AND 
        (lookup.normalized_number = '+......' OR 
         lookup.len <= 11 AND 
         substr('.....', 11 - lookup.len + 1) = lookup.normalized_number OR 
         (lookup.len > 11 AND 
          substr(lookup.normalized_number, lookup.len + 1 - 11) = '.....') ) ) 
 ORDER BY length(lookup.normalized_number) DESC

标签： androidcontacts

解决方案

Thanks all,I've read source code.I found that 'highly optimized' means database level optimization instead of code level optimization.In more detail, Android create several nonclustered index in the phone_lookup table to improve query speed. https://blog.csdn.net/skysukai/article/details/84632943

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