Java is an object-oriented language and runtime environment. Java programs can run unchanged on most platforms in a Virtual Machine called the JVM.

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1answer
737 views

Do Oracle databases use Java internally?

My question is fairly simple. Is Java used internally by Oracle in their DBMSs?
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2answers
4k views

Oracle 11g: performance improvements of inserts

I have a table of 500 millions of rows (and growing) I did the following to improve performance of inserts: On database side: dropped all indexes and constraints disabled logging On application ...
5
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2answers
1k views

Postgresql 9 speeding up indexed inserts (JPA)

I have an application which generates a lot of data which needs to be inserted quickly (something around 13million records). I use JPA 2.0/Hibernate with Postgres 9.1, and I managed to achieve quite a ...
5
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3answers
4k views

Bulk database update/insert from CSV file

I am implementing application specific data import feature from one database to another. I have a CSV file containing say 10000 rows. These rows need to be inserted/updated into database. There ...
4
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2answers
10k views

How to view contents of table in mysql-workbench

Hi everyone am fairly new to mysql, I made a java program that stores data in mysql database. I am using this tool called mysql-workbench that can create databases, tables and much more. What I wanted ...
4
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0answers
124 views

Postgresql JDBC Table Valued Parameters [closed]

MSSQL has a great feature called Table Valued Parameters. It allows you to pass a table of a custom data to stored procedures and functions. I was wondering what is the equivalent in PostgreSQL, if ...
3
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1answer
29 views

duplicate key violates unique constraint when using multi-threading

I am using ExecutorService with a fixed thread pool of 50, and a fixed database connection pool of 50, using HikariCP. Each worker thread processes a packet (a "report"), checks if it is valid (where ...
3
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2answers
297 views

Query for fetching records from SQLite database on Blackberry

I want to fetch data from SQLite database for Blackberry. There is one table with four columns: ID, FROM, TO, TIME I want to fetch record on the basis of FROM, and TO values. Where condition 1: ...
3
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1answer
414 views

Table was not locked with LOCK TABLES when recreating an index

I have a weird problem when recreating the index. This is what happens. This is done through JDBC, in Java btw. A table 'stuff' is truncated by a process. The application is reinitalizing a cycle ...
3
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1answer
1k views

how to use “mysqld -O thread_stack=#”

I keep getting this error whether I run my query from the terminal or from within Java. Anyone has some instructions how to resolve this? Thread stack overrun: 5768 bytes used of a 131072 byte ...
3
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1answer
423 views

How to separate out individual sql statements from Oracle SQL script for execution from java code

I have Oracle DB 11g Enterprise Edition and I want to execute sql script from my java code. I am reading this sql script from a .sql file and the script contains statements such as create table, ...
2
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3answers
94 views

Performance difference between searching table with 350 columns and searching table with 25 columns

I am currently doing some hibernate performance test. My requirement is to search for data in a particular column of a table containing 8 million rows and 350 columns. Currently, I don't have the ...
2
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1answer
123 views

Can I use a Clob as a table key (from Java)?

Following a suggestion made to another question to store large amounts of text: can one use a CLOB as primary key field (i.e., from Java's DataNucleus implementation of JDO)? I know it is probably a ...
2
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1answer
430 views

Return ResultSet with column names from postgresql Stored procedures

I have the following postgresql Function: CREATE OR REPLACE FUNCTION readMessage(messageFor INT, qid INT = NULL, ctxt INT = NULL, messageFrom INT = NULL, byTimeStamp BOOLEAN = FALSE) RETURNS SETOF ...
2
votes
1answer
837 views

Replicate or Call java encryption function in Oracle pl/sql

I am trying to replicate encryption/decryption method present in java in Oracle DB, so that data encrypted in java can be decrypted through Oracle Function. Below is java code: package com.encr; ...
2
votes
2answers
452 views

how to insert multiple columns(around 40) into my sql database using java

i have a program to read the content of an excel file to my-sql db. i have 40 columns in excel and i created a table of 40 fields. and i want to import the data from excel into corresponding table ...
2
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2answers
2k views

java.sql.SQLException: Login failed for user 'sa'

I am having trouble connecting to my SQL Server database through a jtds connection: Connection conn = DriverManager.getConnection("jdbc:jtds:sqlserver://localhost:1433/MnA;instance=SQLEXPRESS", ...
2
votes
1answer
926 views

Derby slows down after 1.2 million records

I'm using a Derby database, mass insertions slow down to 1/4 to 1/6 the speed once there are 1.2 million records (about 6 GB database size, one major table, other tables are tiny). Is that normal? Is ...
2
votes
1answer
57 views

What are possible causes for consistently volatile INSERT performance in MySQL tables?

I have a Java program running on a VM that is sequentially feeding a queue of single row INSERTs through a single connection to a MySQL server on the same VM. The queue execution is not artificially ...
2
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0answers
243 views

Insert Speeds for large batches

In my application, my INSERTs seem to be taking a major chunk of the time. I have a large number of objects in memory (~40-50,000) which i want to insert into a table. Lets take a sample table ...
1
vote
2answers
827 views

Oracle 11. Updating BLOB field. Db file sequential read inappropriately slow?

I've and Oracle (11 Enterprise) schema with a table CREATE TABLE USER.WSP_BUNDLE ( NODE_ID RAW(16) NOT NULL, BUNDLE_DATA BLOB NOT NULL ); CREATE UNIQUE INDEX USER.WSP_BUNDLE_IDX ...
1
vote
1answer
259 views

Is there any way to retrieve “Messages” in SQL Server through JDBC?

By "Messages" I mean the Messages tab in the following figure, which includes "Warning", "n rows affected" and in the figure below, the execution time. In JDBC, ResultSet class is used to retrieve the ...
1
vote
1answer
502 views

What does the bit data type map to in a Java Domain Object

When you have a column of the bit data type what Class would be used to represent that in a Java POJO mapping that table to an object which is using javax.persistence annotations? I tried Boolean, ...
1
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1answer
2k views

Error calling stored procedure from trigger in Oracle Database 11g

I'm trying to create a trigger that calls some Java code whenever a table is inserted/updated. I'm aware of possible performance issues, I don't need advice that I should not do this; I just need to ...
1
vote
3answers
2k views

How to migrate from MySql to HSQLDB?

I have large amount of data in a MySQL database. There are many databases schemas in the database. How I can migrate from MySQL to HSQLDB? Is there some tool for this? I've exported the data ...
1
vote
1answer
854 views

Oracle XE 11g (ORA-12514: TNS:listener does not currently know of service requested in connect descriptor )

I have already seen the questioned in the stack overflow that might relate to my problem but let me emphasize that none of them could resolve my issue. issue is: when I wanted to integrate OWASP ...
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2answers
2k views

How can I execute a PL/SQL procedure for Oracle via JDBC?

I have a Java webapp with an Oracle DB, and I try to execute this statement at the end of a data migration script: EXEC DBMS_STATS.GATHER_TABLE_STATS (ownname => 'MY_SCHEMA', tabname => ...
1
vote
2answers
413 views

Derby/SQL - How to increase performance when left joining and retrieving varchar columns

Through trial and error I found that if I do a left join such as: SELECT firsttable.id, secondtable.id, secondtable.varcharColumn FROM firsttable LEFT JOIN secondtable ON ...
1
vote
1answer
26 views

How does Sybase store datatime information?

We have a Sybase database that currently stores datetime values in some of the tables. If we move that server with the Sybase database to another country which is in another time zone, will the ...
1
vote
2answers
293 views

Exploring and optimizing SQL performance of your system (PostgreSQL and Hibernate)?

Imagine you have inherited some project with extensive usage of SQL queries. Let us assume that Hibernate is used as ORM and PostgreSQL as database, but thats not the point. A question is: could ...
1
vote
1answer
280 views

Convert the IP Address range to two BIGINT for faster lookup

I am working on a project in which we need to do IP Address lookups. So for this we have got the datasets which will look like below and now the next steps is to populate this datasets in to the MySql ...
1
vote
1answer
117 views

Command line switch to disable Coherence?

We have a Java app that happens to have the coherence jar in the path. My application doesn't need it, so I'd like to pass some type of -D variable to the JVM to tell it to ignore coherence, or ...
1
vote
1answer
204 views

MySQL not returning successful results on statement - query looks like it's hanging but is successful

So we have a script(s) that runs in succession. Randomly this task would halt/freeze and error out simply because it did not see a returned response from the MySQL server saying the statement ran ...
1
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1answer
416 views

Unable to connect to MySQL cluster database

I am unable to connect to mysql cluster database after starting my management node, data node, mysql node. I made the necessary changes by adding the loadbalance in the dbURL. But I am not able to ...
1
vote
1answer
652 views

The Database Session is automatically Getting Killed

I am running a java program which connects to the oracle db and retrieves some information. The program contains 12 threads, each thread interns execute sql select commands with multiple join ...
1
vote
1answer
107 views

SpringData MongoDB - infinite getmore on mongo logs

Doing 2 queries on MongoDB through Spring Data on around 160 000 rows, query 1 is executed in few seconds (about 20 results) but query 2 never finish. I'm getting this line over and over on mongodb ...
1
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0answers
79 views

how do I debug postgresql 9.1 server terminating

my /var/log/postgresql/postgresql-9.1-main.log shows 2014-03-25 10:39:30 CET HINT: In a moment you should be able to reconnect to the database and repeat your command. 2014-03-25 10:39:30 CET LOG: ...
1
vote
0answers
35 views

Database tuning and possibly unexpected results

(This is cross-posted from stackoverflow; I initially put it in the wrong place.) So I have a database that's working a bit slower than I would expect and I'd like to describe what I'm doing so ...
1
vote
0answers
368 views

h2 Java server synchronization and caching

I'm happily coding a client-server application in Java using H2 as database. The server runs the database as an embedded local database while clients connect to it via TCP. Now more and more I see ...
1
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0answers
309 views

jTDS + stored procedures + prepareSQL = nesting level error?

Situation A (Tomcat) Java web application using jTDS to connect to a MSSQL 2008 database. This Java application for 99% executes MSSQL stored procedures using user input. Problem The jTDS driver ...
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0answers
415 views

Cannot remove .bak file

I have a java application that: Reads a .bak file from a windows fileshare and restores it in SQL Server on a remote windows server Does various modifications on the database restored from the .bak ...
1
vote
0answers
228 views

Populate database column with drop-down menu item

I'm quite new to Apex and Oracle in general, but I would like to know how to populate a database column with the data from the drop-down list Currently I'm not getting further than simply creating ...
1
vote
0answers
211 views

mysql server is not sending result set back after query execution to client and staying in sending data state

When I pass a query from my Java application to mysql server, it stays in Sending Data state and not returning result set back to application. When I execute the same query in SQLYog directly, it ...
1
vote
0answers
78 views

Altering an Apache Derby table's derby.storage.pageSize property after creation

Is it possible to change the derby.storage.pageSize property of an existing table? Or do I have to export my data, drop then re-create the table with the new property, and then re-import my data?
0
votes
2answers
883 views

java.sql.SQLException: Login failed for user 'sa'

I am having trouble connecting to my Microsoft SQL Server database through a jTDS connection: Connection conn = DriverManager.getConnection("jdbc:jtds:sqlserver://localhost:1433 ...
0
votes
1answer
106 views

Why the table gets deleted by the server in mysql?

I have a table in mysql. I have one java application which will keep inserting the data into this table. So the size of the table grows drastically and at one point it gets deleted automatically by ...
0
votes
1answer
1k views

How to retrieve data from Postgresql index using java

I am writing an application for searching, using text search of Postgresql. I am a beginner in Database. I created a Gin index and i am trying to get data from it. My code is import ...
0
votes
2answers
840 views

Reloading .sql file from java into PostgreSQL - Windows

I am trying to reload a .sql script file into PostgreSQL from my sample Java application. Script is successfully executed from console as well as from pgAdmin tool. But from Java, it hangs... This ...
0
votes
1answer
226 views

Is any possible way to get warning message through by oracle [closed]

I am working in developing oracle data base tool, I want display warning message when executing function. For example: CREATE OR REPLACE FUNCTION FN_OEDS_CONVERTDATE2( V_DATE DATE) RETURN VARCHAR2 ...
0
votes
1answer
23 views

Transforming Huge Database table to Another Table

We are migrating lot of data from our old database to new database. Presently, both of them are actively[writing/reading] used based on flows/activity as migration is in progress. Here's the real ...