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SQL problem

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I have a text (it is a directory) I would like to find in a DB.

My SQL which is OK

 FDQuery4.SQL.add('WHERE MainDirectory LIKE ''%' + jvDirectoryEdit1.Text + '%'''

Now to the problem

If my DB text is  G:\Delphi Projects\image32_3.2.2\

and I am looking for 

G:\Delphi Projects\image32_3.2.2\


G:\Delphi Projects\image32_3 

My above statement finds it NO PROBLEM

HOW EVER if my search is

G:\Delphi Projects\image32_3.2.2\Examples\Layers101

My above line does NOT find it.

What I also tried is using CHARINDEX which I may be did not use correctly


So w.hat I am looking for is search text WITHIN my DB text

Any idea thanks



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Could there be some sort of escape handling kicking in?

Is it necessary to pre-process the text you send as parameter to ensure it is correctly handled by SQLite?

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@Lars Fosdal NO escape but i see there are 2 more possibilities

SUBSTRING and  containing


containing does not work unless i do not know how to use it


Edited by limelect

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@Lars Fosdal this F7 full statement output that works


'Select SectionsId,MainDirectory,MyDateTime,ProjectName,ProjectrealName,Category,FileMask ,Description,FilesIndex'#$D#$A'from Files,Projects'#$D#$A'WHERE MainDirectory LIKE ''%G:\Delphi Projects\image32_3.2.2%''AND SectionsId=FilesIndex'


As you see no problem

Edited by limelect

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@Lars Fosdal Unfortunately all those 'like' explanations are known to me


Or would you like me to make a small DB source to examine the problem?

and put it here?

Edited by limelect

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yes just add a few characters to the text and it will not find the item (a record)

and this is what I want or delete some text and it will find

see my first  writings WITHIN my DB text

7 minutes ago, Lars Fosdal said:

The example does not exemplify the problem.


Edited by limelect

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Maybe I will clarify my problem I add the base directory to the database.

But this directory has many subdirectories and if one searches for a subdirectory

he still needs to find the main directory. This is why

my search is like that.


Do you think there is another way to solve the problem?

Edited by limelect

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My bad for not reading your example closely enough.


The problem is that you are not searching for a substring

%G:\Delphi Projects\image32_3.2.2\Examples\Layers101% is a superset that contains values that are NOT in the database.  

You want to find out if your DB text is contained in your parameter - which is completely different thing.


  FDQuery1.SQL.add('Select MainDirectory');
  FDQuery1.SQL.add('from Files');
  FDQuery1.SQL.add('WHERE INSTR(''' + Edit1.Text + ''', MainDirectory) > 0');

The above will return lines where the MainDirectory strings are found as part of the string in Edit1.Text.

  • Like 1

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Delete some chare and it WII NOT find part of the text

The Like finds if you delete some char

INTR find if you add char

maybe i will try to OR both

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  FDQuery1.SQL.add('WHERE (MainDirectory LIKE ''%' + Edit1.Text + '%'') OR INSTR(''' + Edit1.Text + ''', MainDirectory) > 0'  );
I will check it on the real software

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why do you need the 2 different compare functions? why not just 


WHERE (A LIKE '%' + B + '%') OR (B LIKE '%' + A + '%') ?


if you read it out loud, everybody beside to you will understand what you want


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Well, it returns me to my original problem OUT OF MEMORY.

I made a crazy software.

In any case, you helped a lot.Thanks

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