I have a Java application set up as a service to do data-mining against ~3GB of data every few hours. I would like this to occur 100% in memory. Ideally I want the application to be isolated from everything; I want it to construct the database, do the mining I need, and tear down the database when it's done. However with HSQLDB, even ...
What is the most efficient way to store large arrays (10000x100) in a database, say, hsqldb? I need to do this for a certain math program that I'm writing in java. Please help. The whole array will be retrieved and stored often (not so much individual elements). Also, some meta-data about the array needs to be stored about the array. ...
What is the best way to implement connection pooling in hsqldb, without compromising on the speed? ...
I have two tables (renamed/refactored for illustrative purposes) with a Many-To-Many relationship in an HSQL database. I want everything to be wiped out when I delete from one side of a Many-to-Many relationship (without querying the table; this is performance critical) Here are my main tables: CREATE TABLE PERSON ( PERSON_ID INTE...
I basically created some tables to play around with: I have Two main tables, and a Many-Many join table. Here is the DDL: (I am using HSQLDB) CREATE TABLE PERSON ( PERSON_ID INTEGER GENERATED BY DEFAULT AS IDENTITY PRIMARY KEY, NAME VARCHAR(50), MAIN_PERSON_ID INTEGER ) CREATE TABLE JOB ( JOB_ID INTEGER GENERATED BY DEF...
OpenOffice ships with HSQLDB. Is it possible to easily import the contents of an OO spreadsheet into the built in database? An added nice to have would be to include the formatting of the cell contents. ie. colors, line feeds, etc. This question has gone unanswered so I'm offering a bounty. Please provide the code to the solution. ...
Short version: assuming I don't want to keep the data for long, how do I create a database programmaticly in HSQLDB and load some CSV data into it to? My schema will match the files exactly and the files do have adequate column names. This is an unattended process. Details: I need to apply some simple SQL techniques to three CSV files...
I'm running the following query in Hypersonic DB (HSQLDB): SELECT (CASE foo WHEN 'a' THEN 'bar' WHEN 'b' THEN 'biz' .... ELSE 'fin' END ) FROM MyTable LIMIT 1 When the number of "WHEN" clauses exceeds about 1000, I get a Java StackOverflowError thrown by the JDBC driver in org.hsqldb.jdbc.Util.sqlException(). Here's the reall...
I am not too familiar with database triggers and/or views. I am currently using PostgreSQL and HSQL; although the database is not too important. I am just wondering if any database offers something like this: I have an (example) table like this: CREATE TABLE DUMMY_TABLE (ID INTEGER, NUMBER INTEGER); I created a view like this: CRE...
I have an HSQLDB database with a generated ID and I want the auto-incrementing values to always be above 100,000. Is this possible with HSQLDB? Is this possible with any database? ...
Is it possible to access an HSQLDB database that is running in server mode from a .net application located on the same computer? There do not seem to be any odbc drivers for hsqldb (freely available). Am I missing it? Sun's jdbc odbc bridge seems to allow connecting to an odbc datasource through a jdbc connection, but I would need the...
Performance is key: Is it better to cascade deletes/updates inside of the Database or let Hibernate/JPA take care of it? Will this effect the ability to query for the data if cascades are inside of the DBMS? I am using HSQLDB if that matters. ...
I'm working on repairing the test suite for a project of ours, which is being tested through Hibernate/DBUnit. There are several test cases which all throw a similar exception from Hibernate, which looks something like this: java.sql.SQLException: Not in aggregate function or group by clause: org.hsqldb.Expression@109062e in statement ...
I usually use SQLDeveloper to browse the database, but I couldn't make it work with hsqldb and I don't know which tables are already created... I guess it's a vendor specific question, and not plain sql, but the point is: how can I see the tables so I can drop / alter them? ...
Anyone ever tried to use Derby or HSQLDB in a production environment? Any good, bad or ugly experiences? ...
I am creating database Entities in my Java application and trying to rationalize between using an Integer or a Long as the class type of the "id" field. I am using Hibernate as my ORM which, in turn, will map this field to a column in the HSQLDB database. My struggle is this: a Long is obviously larger and will handle a greater number o...
What are the main differences between SQLite and HSQLDB? There are lots of applications using both of them, but I don't really see any major difference. ...
My team uses a shared instance of Oracle for development using C#, NHibernate and ASP.NET, and we occasionally step on each others toes when making data or schema changes holding up everyone. On another project I'm using Java and HSQL in 100% in-memory mode and just have Hibernate launch a script to import enough data to test with. It...
I have an open source Java application that uses Hibernate and HSQLDB for persistence. In all my toy tests, things run fast and everything is good. I have a client who has been running the software for several months continuously and their database has grown significantly over that time, and performance has dropped gradually. It final...
I have tried SQLite in Java, but the speed is slow due to the JDBC driver. Then I tried HSQLDB and thought the speed is good, but I cannot find a good management tool for HSQLDB such as phpMyAdmin for MySQL or SQLite Manager for SQLite. I'd like to use the manager tool to prepare the test data for unit tests, or use the manager tool to ...