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Pour les possesseurs de DataCheck, voici un message de Paul Carnine, auteur de DataCheck :
I have been investigating issues related to boolean indexes.
I wanted to get back to you all to let you know that I have uncovered some
issues with both indexed and non-indexed use of QUERY after you have
modified the type of a field from integer to boolean.
To be very specific:
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NON-INDEXED FAILURE:
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* In any version of 4D after v6 (6.0 -> 6.8.2)
(NB: v2.2.3 works, I have no key disk for v3.5).
* If you have a field of type Integer.
* If that field has values that are NOT 1 or 0.
* If you convert that field to type Boolean.
* If the field has no index
* If you Query on that field.
Your non-indexed query will fail.
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INDEXED FAILURE (poorly formed index):
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* In any version of 4D/4D Tools that can use fast-mode (6.5.2 -> 6.8.2)
* If you have a field of type Integer.
* If that field has values that are NOT 1 or 0.
* If you convert that field to type Boolean.
* If you build the index using "Fast Index"
Your index query will fail (poorly formed index).
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DEFINITIONS
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"Fast Index" mode is used:
1) when you select it when manually building an index
2) when you use SET INDEX with a "mode" parameter.
3) when you use 4D Tools (compact, rebuild, etc).
"Failure" means:
1) Specifically:
QUERY($pTable->;$pField->;#;True;*)
QUERY($pTable->;$pField->;#;False)
returns records.
this query should always return no records.
2) In your data bases:
Undefined results for any query
against boolean fields.
3) Any version of DataCheck shows index as damaged
(reported as item [75])
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HOW TO REPRODUCE
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I have a very simple v6.8.2 mac database which exhibits the issue:
1. Open the structure with 4D 6.8.2
2. Follow directions you are "alerted" to do.
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HOW TO DETECT
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1) FAST:
Use DataCheck v3.1.2 (available now).
Problem is specifically detected; Reported.
Use DataCheck v2 (for those who have not upgraded):
check "Type Mismatch Warnings" on "Records" tab.
if a field has "Mismatch" and it is a Boolean, the
problem may exist.
NOTE: Any version of DataCheck will complain
when the index is poorly formed.
2) SLOW:
For ($table;1;Count tables)
$pTable:=Table($table)
For ($field;1;Count fields($table))
$pField:=Field($table;$field)
GET FIELD PROPERTIES($pField;$type)
If ($type=Is Boolean )
QUERY($pTable->;$pField->;#;True;*)
QUERY($pTable->;$pField->;#;False)
If (Records in selection($pTable->)>0)
$name:="["+Table name($pTable)+"]"
$name:=$name+Field name($pField)
ALERT("Bad bool query on "+$name)
End if
End if
End for
End for
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WORK AROUND
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For each table that has a problem,
run APPPLY TO SELECTION, rebuild index.
field for APPLY TO SELECTION should not matter.
Here's how you'd do all tables (brute force):
For ($table;1;Count tables)
$pTable:=Table($table)
$pField:=Field($table;1)
ALL RECORDS($pTable->)
APPLY TO SELECTION($pTable->;$pField->:=$pField->)
End for
now rebuild your indexes on those boolean fields.
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SUMMARY
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Thanks to Bernd and Mark for putting me on the scent.
I am in contact with 4D and will do my best to help a fix for this get into
the next maintenance release of 4D.
--
Paul Carnine
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