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Thunderbird search limitations

  • 3 replies
  • 1 has this problem
  • 3 views
  • Last reply by 12199don

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My questions are for someone who is familiar with the specifications for the different search methods and good practices for maintaining the Thunderbird Mail files and the overall SQLITE database.

I am using Thunderbird v91.4.1 for Windows 10 64 bit. Almost all of the mail in my profile was imported from Outlook Express. I’ve been using TB only since August 2021. I rebuilt the global database before doing the searches I report here.

I used two different search methods: -“global search” using the text box (as described at ...kb/Global-Search) -“advanced search” using the Search Messages dialog box (activated by ctrl-shift-F or at the submenu Edit-Find-Search Messages..).

I chose as my search term a 6-letter company name that appears frequently in my emails. I found the following:

Global search returned its results very quickly, finding 979 messages that mentioned my search term. Unfortunately, the timeline covered only from 9/2020-12/2021.

Advanced search #1, using the Boolean OR filters “match any of the following” <Subject contains MySearchTerm> <Body contains MySearchTerm> This took a few minutes but returned 10854 matches spanning dates 2004-2021. Note that this is a narrower search than Global search because I did not include Boolean OR for additional message fields.

Advanced search #2, using the filter <Subject contains MySearchTerm> took only 1-3 seconds and returned 1161 matches spanning dates from 2009 to 2021.

Advanced search #3, using “match any of the following” <Subject contains MySearchTerm> <From, To, CC, or BCC contains MySearchTerm> took about 10 seconds and returned 2214 matches spanning 2009-2022. While this was running, messages appeared in the status line saying something like “building Mail Summary File for folder XYZ”.

It is apparent that the Global Search results are incomplete. Since the high level user documentation says “The search is performed in all fields in all messages: subject, message body, From address, To address, etc. The search is not case-sensitive”, there must be hidden limitations in Global Search. I want to understand this so that I can use Global Search intelligently.

Question 1: What are the limitations of Global Search as compared with Advanced Search? Possible restrictions to consider are: -the search domain -the number of results that can be returned -a time limit for searching -other

Question 2: Is my Mail file set messed up? Looking at the Mail files in Windows Explorer, I found 1465 items in the Outlook Express Import folder, consisting of: 30 subfolders (*.SBD), 873 MBox files (*.) and 562 *.MSF files. Some MBOX files have no MSF file, some have 1 MSF file dated today, and some have 2 MSF files, where an earlier file was in a higher folder and the second file was created today in the same folder as the MBox file. 496 MSF files are dated 1/2/2022 and are located in the same folder as the corresponding MBOX file 66 MSF files are dated 9/3/2021 are located in the folder one level up from the corresponding MBOX file.

Question 3: Is there a semi-automated way to delete all the MSF files and recreate them in their proper locations?

My questions are for someone who is familiar with the specifications for the different search methods and good practices for maintaining the Thunderbird Mail files and the overall SQLITE database. I am using Thunderbird v91.4.1 for Windows 10 64 bit. Almost all of the mail in my profile was imported from Outlook Express. I’ve been using TB only since August 2021. I rebuilt the global database before doing the searches I report here. I used two different search methods: -“global search” using the text box (as described at ...kb/Global-Search) -“advanced search” using the Search Messages dialog box (activated by ctrl-shift-F or at the submenu Edit-Find-Search Messages..). I chose as my search term a 6-letter company name that appears frequently in my emails. I found the following: Global search returned its results very quickly, finding 979 messages that mentioned my search term. Unfortunately, the timeline covered only from 9/2020-12/2021. Advanced search #1, using the Boolean OR filters “match any of the following” <Subject contains MySearchTerm> <Body contains MySearchTerm> This took a few minutes but returned 10854 matches spanning dates 2004-2021. Note that this is a narrower search than Global search because I did not include Boolean OR for additional message fields. Advanced search #2, using the filter <Subject contains MySearchTerm> took only 1-3 seconds and returned 1161 matches spanning dates from 2009 to 2021. Advanced search #3, using “match any of the following” <Subject contains MySearchTerm> <From, To, CC, or BCC contains MySearchTerm> took about 10 seconds and returned 2214 matches spanning 2009-2022. While this was running, messages appeared in the status line saying something like “building Mail Summary File for folder XYZ”. It is apparent that the Global Search results are incomplete. Since the high level user documentation says “The search is performed in all fields in all messages: subject, message body, From address, To address, etc. The search is not case-sensitive”, there must be hidden limitations in Global Search. I want to understand this so that I can use Global Search intelligently. Question 1: What are the limitations of Global Search as compared with Advanced Search? Possible restrictions to consider are: -the search domain -the number of results that can be returned -a time limit for searching -other Question 2: Is my Mail file set messed up? Looking at the Mail files in Windows Explorer, I found 1465 items in the Outlook Express Import folder, consisting of: 30 subfolders (*.SBD), 873 MBox files (*.) and 562 *.MSF files. Some MBOX files have no MSF file, some have 1 MSF file dated today, and some have 2 MSF files, where an earlier file was in a higher folder and the second file was created today in the same folder as the MBox file. 496 MSF files are dated 1/2/2022 and are located in the same folder as the corresponding MBOX file 66 MSF files are dated 9/3/2021 are located in the folder one level up from the corresponding MBOX file. Question 3: Is there a semi-automated way to delete all the MSF files and recreate them in their proper locations?

All Replies (3)

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Despite your great level of detail, unless I am mistaken you have not provided the actual search terms used. That information is essential to providing a useful reply.

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Thanks for your prompt reply. MySearchTerm was "Barker".

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Further investigation of Question 1 at my end found there is a setting that limits the number of messages displayed: mailnews.database.global.search.msg.limit 1000

In practice, the number displayed is not 1000, but ranges from about 940-960. It appears that the messages displayed are the most recent, but it is not clear whether all folders are searched.

Modified by 12199don