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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11
votes
1answer
350 views

MySQL Commited data not seen to select query

Context: The framework used is Spring and all queries are run with JdbcTemplate. Mysql Server version is 5.6.19. The table is an InnoDB table and defaults like auto commit and isolation level ...
10
votes
1answer
1k views

Do Oracle databases use Java internally?

My question is fairly simple. Is Java used internally by Oracle in their DBMSs?
7
votes
2answers
9k 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 ...
6
votes
3answers
23k 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 ...
5
votes
3answers
10k 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 ...
5
votes
3answers
2k 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 ...
4
votes
2answers
3k 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 ...
4
votes
1answer
4k 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 ...
4
votes
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 ...
4
votes
0answers
529 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
votes
1answer
2k 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 ...
3
votes
2answers
2k views

Add function parameter to SQL query WHERE clause

I have a web application in java and it uses a query. I don't want to write the query into Java, so I made a function: CREATE OR REPLACE FUNCTION testFunc(inputs text) RETURNS TABLE(...) AS $$ ...
3
votes
2answers
7k 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 => ...
3
votes
1answer
2k 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 ...
3
votes
2answers
372 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
votes
1answer
185 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 ...
3
votes
1answer
858 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
votes
1answer
2k 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
votes
3answers
191 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
votes
2answers
1k 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, ...
2
votes
2answers
417 views

Database-agnostic stored procedure call passing array of name/value pairs

Background Looking to pass a set of name/value pairs into a stored procedure in a database-agnostic way, using JDBC. A database structure is defined as follows: CREATE TYPE array_parameters AS ( ...
2
votes
1answer
217 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
votes
1answer
109 views

at least one member of a list within another list when querying over a join

Assume the following layout in a MySQL database Activity (id,etc) [id is primary key] AcitivityMapper (activityID, targetYearID) [composite key] Years (targetYearID, targetYearName) [id primary key, ...
2
votes
1answer
2k 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
776 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
votes
1answer
806 views

Sorting Table and get Position of row

I have a Table with 3 rows. Player, Time, Server. Now, I want 2 things and I don't know how. For Server there are 3 worths available. 1, 2 and 3. Server and Player are a Primary Key together. User ...
2
votes
1answer
961 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 ...
2
votes
2answers
3k 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
2k 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
0answers
45 views

Error in loading data using DB2 load command in DB2 10.5

I have a IBM DB2 database in our application. We have a monthly Java batch process which loads data in the tables using "load Replace" sql command. Around millions of record will be updated every ...
2
votes
1answer
131 views

How to connect DB2 with eclipse on mac?

I tried to connect the DB2 Express-C Version 10.1 to Eclipse Mars but it returns an exception when I tried to run the program. com.ibm.db2.jcc.am.DisconnectNonTransientConnectionException: Error ...
2
votes
0answers
61 views

Does SQLJ really specify the charset encoding for deployment descriptor files? [closed]

short topic introduction (for some this will be familiar). "SQLJ" or "SQL/JRT" is Part 13 of the ANSI SQL standard, defining how to do SQL stored procedures and user data types using the Java ...
2
votes
1answer
74 views

Set oracle workspace from java application

I'm connecting to an Oracle database 12c which uses Oracle Workspace Manager from a java application. I'm trying to execute the following command from my java application EXECUTE ...
2
votes
1answer
94 views

Oracle: REGEXP_LIKE: Strings with angle brackets aren't found (whether they are escaped or not)

The following question will answer my original question, plus many others. What would the correct syntax be to do a REGEXP_LIKE search (in Oracle Database 12c) for this string (which exists somewhere ...
2
votes
0answers
1k 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
vote
1answer
502 views

Syntax error using preparedstatements with postgresql

I have a Java application connecting to a PostgreSQL database. Using straightforward code like: ps = con.prepareStatement(sql); if (dataTypes != null && dataTypes.size() ...
1
vote
2answers
2k 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
5k 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
4answers
4k 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
4answers
253 views

Pros and cons of a particular DB design approach for single vs multiple tables

I just got a new project (in JAVA) where I am thinking of all the pros and cons of a particular DB design approach. Some pointers: Our app has many "content" entities like News, Blogs, CMS pages, ...
1
vote
1answer
463 views

Transfer all read request to Slave in Master-Slave MySQL

I have configured master slave on my system (MYSQL). Now, is there is any script or way available or possible to transfer all read request to SLAVE. So, let me make my question here more clear. I ...
1
vote
1answer
12k 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 ...
1
vote
2answers
2k 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
12 views

mysql off-site replication ( file only )

I am new to mysql, I have extensive experience with MS Access and some with Tivoli. I have tried to search the net for my solution but there is such a massive quantity of results I can't find a ...
1
vote
1answer
222 views

How to drop java source from Oracle properly?

I'm a little stuck here with my Java Source. First I want completly drop it from the database, because I want to recompile it, but I can't drop is, because if I execute this command: drop java ...
1
vote
1answer
67 views

JDBC prepared statement - make a token null

So, I have an insert statement in a Java program I'm writing. Under some conditions, I want it to insert some values as null. However, before I can execute the statement, I have to set all of the ...
1
vote
1answer
176 views

SQL Server 2012 CPU usage spikes to 100%

I am using SQL Server 2014 in AWS and the AWS image configuration is 4 cores and 16GB RAM(m3.xlarge). I am running the following simple query, SELECT * FROM user_table WHERE user_id = '10' ...
1
vote
2answers
292 views

Are there any special characters that are never allowed in SQL?

I am a Java programmer. We always make database-related things configurable so that they can be easily modified by the DB team as per their requirements. I want to make some queries as configurable, ...
1
vote
2answers
275 views

Getting a Deadlock,

I have this code : public void saveItems(List<Pair<Item, MapleInventoryType>> items, int id) throws SQLException { PreparedStatement ps = null; PreparedStatement pse = null; ...
1
vote
1answer
929 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 ...