Questions tagged [java]
Use ONLY if Java is directly relevant to the question and likely to be the source of your problem, not just because you're using a Java library to connect to a database. Java is an object-oriented language and runtime environment. Java programs can run unchanged on most platforms in a Virtual Machine called the JVM. If you have a general programming question about Java, please ask it on Stack Overflow instead.
242
questions
-1
votes
0
answers
15
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File path. File not found [closed]
Hi anyone can help me here.
so the problem is that the webapp can't find the file
for example.
if HelloWorld.txt is inside First_Folder, the file can be viewed.
if HelloWorld.txt is inside ...
- 1
0
votes
1
answer
51
views
Oracle DB - can it run without JDK, JRE that is installed together with?
Our client is scanning for outdated JDKs or JREs and found those in Oracle DB instance files, installed files.
Is it safe for Oracle DB to remove JDK, JRE?
Name="Java(TM) SE Runtime Environment&...
- 157
0
votes
0
answers
15
views
Java Inheritance - Hibernate6 + JPA - How to prevent selecting all child tables when joining on parent?
I'm working on a Java application that uses Hibernate6 + JPA.
I have classes like
class Thing {
Parent parent
}
class Parent {
}
class ChildA extends Parent {
}
class ChildB ...
- 9
1
vote
0
answers
27
views
Possible explanation for why "SELECT" query executed from JDBC returning just the first row in the table
I installed OracleDB(XE - free version) and I tried to use it in Java. I have this code:
static final String DB_URL = "jdbc:oracle:thin:@localhost:1521/XE";
static final String ...
- 111
0
votes
0
answers
59
views
Oracle database connection performance dropped to bottom, causing severe performance issues in web application and scheduler job failures
We have some batch scripts as task scheduler jobs, which are running good from few years. These jobs connects to DB and will do multiple inserts and update operations using sqlplus, sqlldr and java ...
Shadowtest
0
votes
0
answers
318
views
SQL*Net message from client too important
It is not easy to describe my problem but I will try. We noticed a slow processing problem with the database when migrating an application from a current VM named VM1 (RedHat 7.9, Java 8, Tomcat, ...
dsea
1
vote
0
answers
238
views
Use 2 columns of a table as foreign key in an other table to avoid circular-reference
I have two tables:
ObjectContainer
containerID INT NOT NULL PRIMARY KEY
mainObjectID INT NOT NULL FOREIGN KEY REFERENCES Object (objectID)
Object
objectID INT NOT ...
- 11
0
votes
1
answer
712
views
Java PostgreSQL library seems to convert dates to local time zone automatically
PostgreSQL 14.6
Ubuntu 22.04
I am using postgresql-42.5.4.jar which I downloaded from pgJDBC. I use this library to get data from a database and display it on a website running locally. The web server ...
- 293
0
votes
0
answers
89
views
Cassandra pod uses more heap memory than configured limit
I set up a Cassandra pod on Kubernetes. I noticed that the following environment variables are ignored by the image, since it goes way beyond 512M memory usage:
env:
- name: MAX_HEAP_SIZE
value: ...
- 101
2
votes
2
answers
504
views
Why does Cassandra lose data when there is an outage on one node with RF=2?
Cassandra works in docker containers.
Cassandra version: 3.11.10.
Cassandra-driver-core: 3.10.2.
Cassandra restart policy: unless-stopped.
Cassandra cluster: 3 nodes.
Keyspace replication factor: {'...
0
votes
0
answers
178
views
how do you condition on column of type jsonb in hibernate
I have a table definition given below filled with random text. I wanted to fetch the records based on the collection of tags. For example, I wanted to pick the records whose tags are 'social' and '...
- 101
0
votes
1
answer
134
views
Can I copy a newer Java JRE over the existing one in Oracle Client 19.16?
A server I manage has Oracle Client 19.16 with Java JRE 1.8_331 installed. Can I just copy a newer version of the Java JRE, like 1.8_351 over the old one without having any negative effect on Oracle ...
- 103
-1
votes
1
answer
1k
views
PostgreSQL claims my query has violated unique key constraint on id [closed]
I'm struggling with an error, and I think it has to do with PostgreSQL. I'm trying to insert values in a database created 3-4years ago. The java program use Hibernate and lombok.
The original program ...
- 117
2
votes
1
answer
974
views
Optimize the number of connections of the connection pool and MySQL
We are using Oracle Cloud's Ampere A1 instance consisting of 4 OCPUs (equivalent to 4 vCPUs) and 24GB of usable memory on Oracle Linux 7.9.
On the server is running an java game server and a web ...
- 23
0
votes
0
answers
107
views
Get index of JSON data in PostgreSQL
I have the next JSON structure in my PosgreSQL:
[
{
"name": "Ryzen 9",
"path": "fitnessappmaven\\src\\main\\java\\com\\klaro\\fitnessappmaven\\tempWorkoutIcons\\...
0
votes
1
answer
529
views
Update specified data in PostgreSQL/ JSON based on 2 conditions
I searched a lot to find solution and I found something similar but unfortunately I couldn't apply it to my case, maybe because I am yet new to Postgres. The link to this similar issue is here:
Update ...
4
votes
1
answer
4k
views
nodetool with Java 8u331 returns "URISyntaxException: 'Malformed IPv6 address at index 7: rmi://[127.0.0.1]:7199'"
Why does running nodetool return the following exception?
nodetool: Failed to connect to '127.0.0.1:7199' - \
URISyntaxException: 'Malformed IPv6 address at index 7: rmi://[127.0.0.1]:7199'.
This ...
- 3,280
0
votes
1
answer
244
views
Oracle 21c XE, need install/enable JServer JAVA Virtual Machine, but ORA-00904
In Oracle 21c XE, I need install/add JServer JAVA Virtual Machine. When I try to install it, there is a problem, exactly ORA-00904: "PSU_VER": invalid identifier.
SQL> @?/javavm/install/...
- 181
0
votes
1
answer
52
views
NDB Cluster Read and Write Process multiple Access
When using the MySQL NDB Cluster distributed database, the following general problem has arisen: To insert a new Record / Row, the last row in the database should be read, see if it is compatible with ...
1
vote
1
answer
566
views
Run MSSQL stored procedures containing SSIS packages using Windows Authentication from another computer
I am new to MSSQL. I have a question about executing MSSQL Stored Procedure.
Let me briefly talk about my development environment first:
PC400 (Computer/Server A), where SQL Server 2012 is installed
...
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1
vote
0
answers
370
views
SSL connection error when connecting to MySQL, using JDBC
The problem that we are facing is well documented in https://stackoverflow.com/questions/34189756/warning-about-ssl-connection-when-connecting-to-mysql-database.
We started facing this issue upon ...
- 255
0
votes
1
answer
68
views
why does external java function terminate recursive cte?
I made a peculiar observation regarding external functions written in java which I hope someone can shed a light on. I tried it with several functions, but I'll use one of them as an example here:
...
- 23.1k
1
vote
2
answers
2k
views
I cannot create a table in mysql
create table Statistics_tbl with (
SELECT Todo_tbl.person, SUM(Todo_tbl.duration) FROM Todo_tbl JOIN Statistics_tbl
on Todo_tbl.person = Statistics_tbl.person GROUP BY person;
);
The issue is that ...
1
vote
1
answer
115
views
How can I join two tables in mysql, so that whenever I add data to table 1, table 2 updates as well?
This is the code creating my first table
create table Todo_tbl (
id INT auto_increment,
person VARCHAR(45) ,
task VARCHAR(45) ,
duration INT(4),
deadline_day VARCHAR(2),
deadline_month VARCHAR(2),
...
0
votes
1
answer
2k
views
How to automatically update table, whenever data added to another table?
I have created two tables in MySQL. One (Todo_tbl) holds the data while the other (Statistics_tbl) hold the sums one of the variables from Todo_tbl.
Following the definitions of these tables:
create ...
0
votes
0
answers
932
views
How to load Java in Oracle Database using SQL Developer?
I'm running Oracle 19.
I would like to load some Java classes using SQL Developer, but the option is greyed out.
Is there any necessary grants to do that? Or is there any other way to do it via SQL ...
- 141
0
votes
1
answer
93
views
When should I use Index on PostgreSQL? [closed]
In my Java (Spring Boot app), I have the following entity definition which has a relationship with Company entity via companyUuid property. I will also let users to search by name field. We do not ...
- 1
0
votes
1
answer
482
views
how do I copy oracle java stored procs from one database to another?
I have an oracle database with some java stored procs. I am creating a dockerized version of the database for our developers to use. I can use oracle sql developer to copy all normal pl/sql procs to ...
- 127
-1
votes
1
answer
103
views
I want to drop existing table space and add the freed space to the new table space in oracle
I want to drop existing table space and add the freed space to the new table space in oracle.
I am trying drop an existing tablespace on oracle db, and then use the freed space for a new table space. ...
- 1
0
votes
0
answers
30
views
Optimal way of running hundreds of thousands of DDL/DML statements MySQL
I have about 500k DDL/DML statements that need to be run against a MySQL 5.7 INNODB RDS instance from scratch. A significant portion of these are created table statements.
I'm currently employing a ...
David
0
votes
0
answers
53
views
SQL connections to java applications
I have an MSSQLServer2000 database that seems to have been working just fine until today. The DB connects to a java application on a remote server that passes the database data (login credentials, ...
- 75
1
vote
0
answers
352
views
Error occurred in Spring boot + Gradle + Oracle jdbc + jsp project
I'm doing Spring boot project, and I'm trying to add dependencies which are ojdbc8 and tomcat-embed-jasper. ojdbc8 library is for connecting Oracle database by using Hikari, and tomcat-embed-jasper is ...
- 13
1
vote
1
answer
4k
views
Can Microsoft JDBC Driver 4.0 connect to SQL Server 2019 and perform DML without issue?
The SQL version compatibility BOL article advises that the minimum compatible JDBC driver version for SQL Server 2019 is 7.4.
Can an older JDBC driver still connect to SQL Server 2019? Or can only the ...
- 1,434
0
votes
1
answer
176
views
What is the format of EXTERNAL NAME argument?
When a Java class cl with a method mth resides in a package pck, what should I put into the EXTERNAL NAME clause of CREATE PROCEDURE?
I tried
CREATE PROCEDURE mth (arg1 INTEGER) LANGUAGE JAVA EXTERNAL ...
- 37
2
votes
1
answer
5k
views
How to configure TCPS in JDBC thin client for oracle
An Java Application running with JDBC thin wtih TCP connection, Now require is to convert in TCPS for encryption transmission from application to database.
String url = "jdbc:oracle:thin:@(...
- 121
0
votes
1
answer
516
views
Queries of MySQL from Java are executed serially from multiple threads
I have REST API developed in spring + java and hosted on Tomcat server. I have a MySQL database where i store all my data. API makes just simple select from db as descripted below. I failed ...
0
votes
1
answer
61
views
does using optimizer_mode=first_rows_n for application that using Oracle database is a best practice?
So I'm working in application that involving display of data in table/grid. And the grid will invoke paging query to oracle. So does by tuning my application to get the best query cost with ...
0
votes
0
answers
47
views
Update table_name set column1 from where column2 (column2 mutiple diffirent value)?
Hi I'm working with this Query to update all the row in the table using a String of multiple values.
I'm trying some Query but i get an error
the error is "Truncated incorrect DOUBLE value"
this is ...
- 13
2
votes
1
answer
574
views
How to determine if Oracle Java classes are being used
Oracle EE 12.1.0.2
As part of a general clean up of a legacy application prior to a migration I'm trying to determine what objects are actually in use.
There are some 230 JAVA class objects in my ...
0
votes
1
answer
627
views
Install Oracle Weblogic: Unsupported major.minor version 52.0 [closed]
I tried to install Oracle Weblogic on Redhat Linux 8
using command
java -jar fmw_12.2.1.4.0_wls_quick.jar
but got an error:
Unsupported major.minor version 52.0
Java version
java version "1.7....
0
votes
1
answer
327
views
how to get data from two tables in mysql query with where Pk of one table is set as foreign key on PK column for other table?
The query I am using to retrieve data is as
"select sum(totalbill) as tbdb, sum(discinamount) as tddb, sum (billafterdisc) as tbaddb,"
+ " sum(totalqt) as tqdb,"
+ " sum(payed) as tpdb,"
+ " sum(...
0
votes
1
answer
235
views
Use quoted schema in an insert statement executed thorough PreparedStatement in Java
I created an unquoted table my_table under a quoted schema "Quoted_User".
When executing the statement
INSERT INTO "Quoted_User".my_table (custom_id) VALUES (DEFAULT)
using the Intellij Oracle ...
-1
votes
1
answer
492
views
pg replication connection not returns wal events to java code client , it hangs some times
Describe the issue
We are facing issue of pg replication slot not listen database wal events.
Once pg database restarted and we attach
Driver Version: 42.2.6
Java Version: JDK1.8
OS Version: Window ...
2
votes
2
answers
3k
views
Does oracle client 12c requires Java on windows
if I install Oracle 12c client on window server, does it get Java installed?
can we install oracle driver/client without Java?
- 183
1
vote
1
answer
356
views
Oracle save mandarin characters with we8iso8859p1
Im trying to save Mandarin characters into Oracle instance database 11g.
Field datatype - NVARCHAR2 ;
NLS_LANG - AMERICAN_AMERICA.WE8ISO8859P1
If I change NLS_LANG, it will affect other data already ...
- 11
-2
votes
1
answer
40
views
Should I use the LIKE predicate or fetch all rows and process them on the client?
I am optimizing my application, while this task, I find one query which is fetching data from database using like .
and database rows are around 10000.
So is this a good way to use like in query or I ...
1
vote
1
answer
185
views
Troubleshooting oracle database errors from cloud application
I am trying to troubleshoot an issue that presents as different database errors such as, ORA-01000: maximum open cursors exceeded or Unable to create DB Connection. I have reviewed the PLSQL to ...
- 111
0
votes
1
answer
2k
views
How to determine/set the Java classpath for an Oracle DB?
l am trying to make use of some proprietary Oracle Java classes/methods using an Oracle provided virtual machine (E-Business Suite Vision, Oracle 12.2.28)
On my test server I define a function:
[...
- 101
0
votes
0
answers
712
views
SQLServer JDBC Driver]Object has been closed
I had few queries in code which were running in loop. They all were wrapped inside a code function. There were frequent deadlock with the queries. Because I do not understand the logic too well, I was ...
- 101
1
vote
1
answer
730
views
Which java JDK is compatible with oracle instant client 10g
I'm an intern stuck trying to retrieve data from Oracle 8i (a database that is as as I am)
The problem:
I need to write a java script that pulls data from Oracle 8i into a newer server. The last ...
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