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https://issues.apache.org/jira/browse/DERBY-1748?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12607604#action_12607604
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Rick Hillegas commented on DERBY-1748:
--------------------------------------

Hi Geoff,

For the gory details, you may want to read the functional spec attached to 
DERBY-481. Here are some responses to your questions:

>1) updates and inserts propagate seamlessly to the generated columns

Yes. Derby will recalculate the values of generated columns if you change 
(insert/update) the values of columns referenced by the generation clause.

>2) dropping the "owner" column can seamlessly cascade to dropping the 
>generated column

The default behavior of DROP COLUMN will continue to be CASCADE, which will 
produce the results you want. This detail is tucked away in the functional spec 
in the "Behavior" section.

>3) any indexes created on the generated column seamlessly disappear when the 
>generated column is dropped 

Yes, this is how it will work.

Hope this helps,
-Rick

> Global case insensitive setting
> -------------------------------
>
>                 Key: DERBY-1748
>                 URL: https://issues.apache.org/jira/browse/DERBY-1748
>             Project: Derby
>          Issue Type: New Feature
>          Components: SQL
>            Reporter: Terry
>
> By default MySQL is case insensitive in its string comparisons, as you can 
> see from the MySQL docs shown below. Similar functionality is available in 
> Sybase iAnywhere and in SQLServer. I'd like the same to be true for Derby.
> What, I wonder, are chances of that?
> I am aware that functions could be used to force comparisons in upper case 
> but that subverts the indexes and makes searches unacceptably long.
> If you were to ask people you might find that this is a feature whose 
> abscence is causing many to look elsewhere.
> thanks for all the great work,
> Terry
> The MySQL Docs say:
> -------- start quote
>  By default, MySQL searches are not case sensitive (although there are some 
> character sets that are never case insensitive, such as czech). This means 
> that if you search with col_name LIKE 'a%', you get all column values that 
> start with A or a. If you want to make this search case sensitive, make sure 
> that one of the operands has a case sensitive or binary collation. For 
> example, if you are comparing a column and a string that both have the latin1 
> character set, you can use the COLLATE operator to cause either operand to 
> have the latin1_general_cs or latin1_bin collation. For example:
> col_name COLLATE latin1_general_cs LIKE 'a%'
> col_name LIKE 'a%' COLLATE latin1_general_cs
> col_name COLLATE latin1_bin LIKE 'a%'
> col_name LIKE 'a%' COLLATE latin1_bin
> If you want a column always to be treated in case-sensitive fashion, declare 
> it with a case sensitive or binary collation. See Section 13.1.5, "CREATE 
> TABLE Syntax". 
>     By default, the search is performed in case-insensitive fashion. In MySQL 
> 4.1 and up, you can make a full-text search by using a binary collation for 
> the indexed columns. For example, a column that has a character set of latin1 
> can be assigned a collation of latin1_bin to make it case sensitive for 
> full-text searches.
> --------------- end quote

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