SQL-query with max lenght

[Marc Vanzegbroeck]

Hi,

I know this is not the right forum for SQL-query's, bet mayme someone know the result.

I have a SQL-table (tagnames) like

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PARAMETER  INHOUD
---------  ------
TAGNAME    AI123
PTDESC     THIS IS A TEST
KEYWORD    A
TAGNAME    AI1231
PTDESC     THIS IS AN OTHER TEST
KEYWORD    ABBB
TAGNAME    AI123456
PTDESC     THIS IS A TEST
KEYWORD    AQ

I would like to return an unique record per PARAMETER and the maximum lenght of field INHOUD
It sould be something like

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PARAMETER  INHOUD
---------  ------
TAGNAME    8
PTDESC     21
KEYWORD    4

I already have tried with

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SELECT parameter,inhoud,length(inhoud) as vlen  from tagnames group by parameter

But this give me the unique PARAMETERS, but not the maximum of the field-lengt of INHOUD

The same with

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SELECT parameter,inhoud,max(length(inhoud)) as vlen  from tagnames group by parameter

How can I do this?
Thanks,

[Enrico Maria Giordano]

Marc,

Code: Select all  Expand view

SELECT parameter,inhoud,length(inhoud) as vlen  from tagnames group by parameter

The query below works fine with Access:

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SELECT Parameter, Max( Len( Inhoud ) ) AS VLen FROM TagNames GROUP BY Parameter

EMG

[Marc Vanzegbroeck]

Marc,

Code: Select all  Expand view

SELECT parameter,inhoud,length(inhoud) as vlen  from tagnames group by parameter

The query below works fine with Access:

Code: Select all  Expand view

SELECT Parameter, Max( Len( Inhoud ) ) AS VLen FROM TagNames GROUP BY Parameter

EMG

Enrico,

You are correct

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SELECT parameter,imax(length(inhoud)) as vlen  from tagnames group by parameter

works fine also with SQLite.
I think I have made a mistake while testing, I used instead of GROUP BY, ORDER BY because i was thinking to order it on length from high to low and than Group them, but GROUP BY and ORDER BY doesn't work in the same select..