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From: "Yifan Wang" <heavenstar@gmail.com>
To: <derby-dev@db.apache.org>
References: <BAY124-DAV13D24F02EB81BB2AC14B01E7570@phx.gbl>
 <4627D222.3030400@amberpoint.com>
Subject: re: How to execute DDL and DML statements concurrently?
Date: Thu, 19 Apr 2007 23:23:07 +0200
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The DDL statements are mostly =A1=B0create=A1=B1 new tables.
In the test, it seems that the problems are not depending on different =
DDL
statements.

Do you mean we change the concurrency level in derby dynamically =
depending
on the statements?

Thanks
Yifan

-----=D3=CA=BC=FE=D4=AD=BC=FE-----
=B7=A2=BC=FE=C8=CB: Bryan Pendleton [mailto:bpendleton@amberpoint.com]=20
=B7=A2=CB=CD=CA=B1=BC=E4: 2007=C4=EA4=D4=C219=C8=D5 22:34
=CA=D5=BC=FE=C8=CB: derby-dev@db.apache.org
=D6=F7=CC=E2: Re: How to execute DDL and DML statements concurrently?

> We find that Derby will lock the data dictionary for a relative long=20
> time when executes DDL statements,

Does it vary based on the DDL statement? Which DDL statements have you
tried, and can you measure differing concurrency levels depending on
the statement?

thanks,

bryan