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From "Thomas J. Taylor" <Thomas.Tay...@Miami.edu>
Subject RE: Derby 10.1 -> 10.2 upgrade issue
Date Thu, 05 Mar 2009 20:38:28 GMT
Kal,

According to the Java 5 docs, the getIndexInfo ResultSet should contain all
of the required information (INDEX_NAME, COLUMN_NAME, NON_UNIQUE) - if the
index consists of multiple columns, then multiple ResultSet entries will be
returned for a given INDEX_NAME, and you'll have to use ORDINAL_POSITION to
recreate the sequencing of columns within the index.

 

If not, you might try looking at the thread/link that Rick Hillegas sent
(http://www.nabble.com/How-can-I-fetch-constraint-attribute-on-Column-Level-
from-SYS-Tables---td19554573.html#a19554573)

 

Thomas

INFOTECH Soft, Inc.

getIndexInfo

ResultSet <http://java.sun.com/j2se/1.5.0/docs/api/java/sql/ResultSet.html>
getIndexInfo(String
<http://java.sun.com/j2se/1.5.0/docs/api/java/lang/String.html>  catalog,

                       String
<http://java.sun.com/j2se/1.5.0/docs/api/java/lang/String.html>  schema,

                       String
<http://java.sun.com/j2se/1.5.0/docs/api/java/lang/String.html>  table,

                       boolean unique,

                       boolean approximate)

                       throws SQLException
<http://java.sun.com/j2se/1.5.0/docs/api/java/sql/SQLException.html> 

Retrieves a description of the given table's indices and statistics. They
are ordered by NON_UNIQUE, TYPE, INDEX_NAME, and ORDINAL_POSITION. 

Each index column description has the following columns: 

1.      TABLE_CAT String => table catalog (may be null) 

2.      TABLE_SCHEM String => table schema (may be null) 

3.      TABLE_NAME String => table name 

4.      NON_UNIQUE boolean => Can index values be non-unique. false when
TYPE is tableIndexStatistic 

5.      INDEX_QUALIFIER String => index catalog (may be null); null when
TYPE is tableIndexStatistic 

6.      INDEX_NAME String => index name; null when TYPE is
tableIndexStatistic 

7.      TYPE short => index type: 

o    tableIndexStatistic - this identifies table statistics that are
returned in conjuction with a table's index descriptions 

o    tableIndexClustered - this is a clustered index 

o    tableIndexHashed - this is a hashed index 

o    tableIndexOther - this is some other style of index 

8.      ORDINAL_POSITION short => column sequence number within index; zero
when TYPE is tableIndexStatistic 

9.      COLUMN_NAME String => column name; null when TYPE is
tableIndexStatistic 

10.  ASC_OR_DESC String => column sort sequence, "A" => ascending, "D" =>
descending, may be null if sort sequence is not supported; null when TYPE is
tableIndexStatistic 

11.  CARDINALITY int => When TYPE is tableIndexStatistic, then this is the
number of rows in the table; otherwise, it is the number of unique values in
the index. 

12.  PAGES int => When TYPE is tableIndexStatisic then this is the number of
pages used for the table, otherwise it is the number of pages used for the
current index. 

13.  FILTER_CONDITION String => Filter condition, if any. (may be null) 

Parameters: 

catalog - a catalog name; must match the catalog name as it is stored in
this database; "" retrieves those without a catalog; null means that the
catalog name should not be used to narrow the search 

schema - a schema name; must match the schema name as it is stored in this
database; "" retrieves those without a schema; null means that the schema
name should not be used to narrow the search 

table - a table name; must match the table name as it is stored in this
database 

unique - when true, return only indices for unique values; when false,
return indices regardless of whether unique or not 

approximate - when true, result is allowed to reflect approximate or out of
data values; when false, results are requested to be accurate 

Returns: 

ResultSet - each row is an index column description 

Throws: 

SQLException
<http://java.sun.com/j2se/1.5.0/docs/api/java/sql/SQLException.html>  - if a
database access error occurs

 

 

From: Kalyan Inuganti [mailto:kinuganti@gmail.com] 
Sent: Thursday, March 05, 2009 1:44 PM
To: Thomas@infotechsoft.com; derby-user@db.apache.org
Subject: Re: Derby 10.1 -> 10.2 upgrade issue

 

Hi Thomas,

I have been doing some research on how i can get the column name(s) that the
index corresponds to (see the 2nd bold section of the SQL) and haven't found
anything yet. Any ideas? I would also like to know if a given index is a
unique index or not? The reason I say this is because I looked at "Create
Index..." statements and there are 2 flavors - ones with the Unique
qualifier and the others without.

statement.executeUpdate("CREATE UNIQUE INDEX "+indexNameString+" ON
DeviceInfo (DeviceID)");

Thanks a lot for your help!
Kal

On Thu, Mar 5, 2009 at 11:15 AM, Thomas J. Taylor
<Thomas.Taylor@infotechsoft.com> wrote:

Hi Kal,

 

I'll check to see if I can find the code/process that I used back then to
solve the issue. Since I only had one (remote) Derby installation causing
problems, once I figured out the way to resolve the problem (drop & recreate
index), I probably (1) used DBLook to identify the corrupt (missing)
indexes, then used SQurilleL to (2) identify the names of the keys through
the GUI, (3) write the DDL to drop and re-create the indexes.

 

You should be able to use JDBC to get the same index information and
drop/create the index that way; however, the challenge is identifying the
corrupt indices. Perhaps this might work?

 

Connection connection; // existing db connection

Statement statement = connection.createStatement();  

try {

     // test table to confirm corrupt index: SQLException is thrown if
corrupt

statement.executeQuery("SELECT DeviceID, DeviceName, DeviceType FROM
DeviceInfo WHERE DeviceID=1");

} catch (SQLException ex) {

     // retrieve index information for the corrupt table

//
http://java.sun.com/j2se/1.5.0/docs/api/java/sql/DatabaseMetaData.html#getIn
dexInfo(java.lang.String,
<http://java.sun.com/j2se/1.5.0/docs/api/java/sql/DatabaseMetaData.html%23ge
tIndexInfo%28java.lang.String,%20java.lang.String,%20java.lang.String,%20boo
lean,%20boolean%29>  java.lang.String, java.lang.String, boolean, boolean)

     DatabaseMetaData databaseMetaData = conn.getMetaData();

     ResultSet resultSet = databaseMetaData.getIndexInfo(null, null,
"DeviceInfo", false, false);

     // for each index, drop & recreate the index

     while (resultSet.hasNext()) {

           // get the name of the 

           String indexNameString = resultSet.getString("INDEX_NAME");

           statement.executeUpdate("DROP INDEX "+indexNameString+" ON
DeviceInfo);

// recreate index:
http://db.apache.org/derby/docs/10.2/ref/rrefsqlj20937.html

           statement.executeUpdate("CREATE UNIQUE INDEX "+indexNameString+"
ON DeviceInfo (DeviceID)");

}

}

 

Thomas Taylor

INFOTECH Soft, Inc.

 

From: Kalyan Inuganti [mailto:kinuganti@gmail.com] 
Sent: Thursday, March 05, 2009 11:10 AM
To: derby-user@db.apache.org
Subject: Derby 10.1 -> 10.2 upgrade issue

 

Hi,

I am reaching out to you guys for some help with a Derby indexing issue that
we have run into at Monsanto, St. Louis. The issue is pretty much the same
issue that was reported by Thomas J. Taylor in 2007 (The link is provided
below). 

Brief Description:

I have a database that was originally created with Derby 10.1.1.0 and was













 
recently upgraded to Derby 10.2.2.0. I've performed this upgrade on several













 














 
copies of the same database schema (each created on different computers,













 
but with the same version of Java (1.5.0_07) and Derby (10.1)).













 














 
For all but one of the database upgrades, it worked correctly. However, in













 














 
one case, it appears that the PRIMARY KEY and FOREIGN KEY constraints have













 
been lost/corrupted. When I use DBLook to check a 'working' database, I see













 
the appropriate constraints for keys. However, on the 'defective' database,













 














 
these constraints are missing.


We have over 80 tables in the DB and over 1000 users. Even though we have
only 2 reported occurrences of this issue so far, it might be more
widespread. It is a nightmare to manually identify the corrupted indexes for
each occurrence. Any thoughts on how we can tackle this through a
programmatic approach?

Here is the link to the old report:

http://mail-archives.apache.org/mod_mbox/db-derby-user/200704.mbox/%3C462D5D
F8.80101@gmail.com%3E

Thanks,
Kal   

 


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