locking issue with a select statement using an order by clause
--------------------------------------------------------------
Key: DERBY-1017
URL: http://issues.apache.org/jira/browse/DERBY-1017
Project: Derby
Type: Bug
Components: Network Server
Versions: 10.0.2.0
Environment: Windows XP Professional operating system and Java2 platform using
JDK 5.0
Reporter: Mark H. Kaplan
I am using the network version of Derby (version 10 - the network version). I
am running two threads. The first thread is doing an insert into a table but
not committing. The second table is doing a select statement. When the select
statement has an order by clause, it will not complete but when it does not
have the order by clause, it completes while the first thread is sleeping.
The database contains one table with five columns. I have tried having an index
on the order by column but that does not seem to make a difference. I have not
set any isolation level on the database so it is using the default of
TRANSACTION_READ_COMMITTED.
The insert statement in the first thread looks like:
INSERT INTO Authors (au_id, au_lname, au_fname, phone, contract) VALUES
('999-99-9999', 'last', 'first', 'xxx-xxxx', 0)
The select statement in the second thread looks like:
SELECT au_id, au_lname, au_fname, phone, contract FROM authors where au_lname =
'xxx' ORDER BY au_fname
MORE INFORMATION --
My order by select statement does timeout with the error 40XL1. I tried putting
an index on the au_fname but that did not make a difference
I have included locking data which I retrieved by running a "SELECT * FROM NEW
org.apache.derby.diag.LockTable() AS LT" while the second thread was doing its
SELECT statement. I do not understand the data but I thought that it might give
you a better idea of what is going on. I have also included the database sql
script that creates the database table and the two sql statements that I am
running in separate threads to give you a better idea of what I am doing. Let
me know if you need any other information:
(Locking Data)
XID |TYPE |MODE |TAB |LOCK |STATE |TABLETYPE |LOCK& |INDEXNAME
===
302 |ROW |X |AUTHORS |(2,18) |GRANT |T |1 |null
302 |ROW |X |AUTHORS |(1,7) |GRANT |T |1 |null
304 |ROW |S |AUTHORS |(1,7) |WAIT |T |0 |null
302 |TABLE |IX |AUTHORS |Tablelock |GRANT |T |3 |null
304 |TABLE |IS |AUTHORS |Tablelock |GRANT |T |1 |null
(SQL Script)
DROP TABLE authors;
CREATE TABLE authors (
au_id VARCHAR(32) NOT NULL,
au_lname VARCHAR(40) ,
au_fname VARCHAR(20) ,
phone VARCHAR(12) ,
contract INT NOT NULL,
PRIMARY KEY (au_id)
);
CREATE INDEX firstnameindex ON authors (au_fname);
(SQL Statements)
Thread 1 - INSERT INTO Authors (au_id, au_lname, au_fname, phone, contract)
VALUES ('999-99-9999', 'last', 'first', 'xxx-xxxx', 0)
Thread2 - SELECT au_id, au_lname, au_fname, phone, contract FROM authors where
au_lname = 'xxx' ORDER BY au_fname
--
This message is automatically generated by JIRA.
-
If you think it was sent incorrectly contact one of the administrators:
http://issues.apache.org/jira/secure/Administrators.jspa
-
For more information on JIRA, see:
http://www.atlassian.com/software/jira
