failure - test failed: the network adapter could not establish the connection - database

I installed oracle 11g in my machine and created tablespaces and user.
Evereything ran succesfully. Now im trying to create a new conenction thru sqlDeveloper but i get this error. I checked the SID name and changed them according to tnsnames.ora. what else might go wrong?

Don't use the tnsnames.ora and set the connection type to "Basic".
Enter your connection details (SID, Port, host, username and password) accordingly.

Use connection type basic, and dont use hyphen "-" in the connection name, while use underscore "_". and then try again to connect

If the database is on your machine, and you're still talking about 11g, then you can simply do this:
Connection Type: Basic
Hostname: localhost (you said it the db was on YOUR machine, yes?)
Port: 1521 (this is the default unless you changed it)
SID: orcl for regular db or xe for Express edition
Service Name: use this if 12c with Pluggable Database
Or course for username and password:
username: system (a default ADMIN account, less dangerous than SYS)
password: whatever you provided when creating your database
If you are going to login as SYS, you must change the Role from default to SYSDBA.
If you have TNSNames.ora file, we should find it, and you can set your Connection Type to TNS, and simply pick your database from the dropdown.
As you can imagine, when you have MANY databases, the TNS path is much easier, but you will need to maintain this file. Otherwise, Basic is the easiest way to go.

Related

Oracle container database 12c, connecting using JDBC

I'm trying to learn how to use Oracle Container database, and just do basic JDBC connections. I installed a dockerised version of Oracle:
https://hub.docker.com/_/oracle-database-enterprise-edition
Which according to the data sheet comes set up with a CDB database called ORCLCDB and a PDB database called ORCLPDB1.
So I figured out I can connect to it like this:
jdbc:oracle:thin:#localhost:1555:ORCLCDB
with username sys, password Oradoc_db1, and setting the special internal_logon jdbc parameter equal to "sysdba" to avoid the error "local oracle CDB: ORA-28009: connection as SYS should be as SYSDBA or SYSOPER"
And I figured out I can switch to the PDB by entering this:
ALTER SESSION SET CONTAINER=ORCLPDB1
And I can then create a new user:
CREATE USER MYUSER IDENTIFIED BY MYPASSWORD1
But then I'm stuck. I think there should be some way to connect directly to the PDB using a JDBC connect string. Every time I google about this, it talks about tnsnames blah blah, but people who use JDBC connections, are typically using Tomcat on a server, or otherwise don't have the Oracle Client installed. They expect to be able to connect to Oracle just with the thin driver installed, nothing else.
I've tried the obvious using:
jdbc:oracle:thin:#localhost:1555:ORCLPDB1
with username myuser or sys, but I always get:
ORA-12505, TNS:listener does not currently know of SID given in connect descriptor
At this point I'm stuck.
You need to use a SERVICE_NAME in order to connect to an Oracle container database
Please alter your connect string like this:
jdbc:oracle:thin:#localhost:1555/ORCLPDB1
A SERVICE_NAME is denoted by a "/"
A SID (SystemIDentifier) is denoted by a ":" (not to be used)
Note! Default listener port is 1521, not sure why you specifically want a different port.
Best of luck!
Apparently the correct answer is this...
jdbc:oracle:thin:#localhost:1521/ORCLPDB1.localdomain
Then I can connect as SYS using the method above. If I want to connect as the created user, I also need...
grant create session to myuser;
and then, turn off the internal_logon jdbc parameter.

Publicly Visible Database Password on Github an issue?

I'm running an express server and I am very new to databases. If I have a public repo on Github of my express server and have this line of code publicly visible in one of the files:
const pool = new Pool({
user: "postgres",
host: "localhost",
database: "postgres",
password: "dummypassword",
post: 5432
});
Can people somehow connect to my PSQL database using my 'dummypassword' and mess up people's accounts that are stored in that database? I am planning to deploy it to DigitalOcean and I am wondering if this could be an issue somehow later down the road.
Thanks :)
If dummypassword is your true database password, then yes, this is absolutely a problem. You would literally be giving hackers instructions on exactly how to connect to your database! Don't do this.
Look into using dotenv on npm. This will allow you to create a .env file that can hold this precious information on a server outside of version control i.e. Github.
https://www.npmjs.com/package/dotenv
To expound on this, I would always err on the side of caution when dealing with database credentials. Say someone did get access to this information but that wasn't the actual database password, but the rest of the credentials were. The intruder now knows what kind of database you are running, where it's located, what port, and the username. All they need is the password in order to gain access to your entire production database and all of your users information.
I'm assuming you are saying; can someone connect to my production database ONCE you have changed the password for your production database?
If so then there is nothing in your example that isn't default so the answer is no.
If you're saying that "dummypassword" will be in production then yes that would NOT be a good idea, but I'm guessing you're not saying that.

What Registration Properties are needed to get Database Workbench up and running?

I am a Database Workbench fan from way back, but bizarrely have not used it for quite awhile.
I downloaded a trial version and am trying to "Register Server" as a first step.
The problem is I don't know what to use for which properties. I need to know:
Alias
Host
Instance
With "Use SQL Server Authentication" checked:
Username
Password
I've tried to guess my way through what is needed where, but nothing has worked.
I can connect to the database in (C#) code with this connection string:
"SERVER=PlatypusSQL42;DATABASE=duckbilldata;UID=youinnocentdog;PWD=contrasena;Connection Timeout=0";
And so I have tried these values:
Alias: DBWBSQLServer
Host: PlatypusSQL42
Instance: duckbilldata
Username: youinnocentdog
Password:contrasena
..and this:
Alias: PlatypusSQL42
Host: duckbilldata
Instance:
Username: youinnocentdog
Password:contrasena
...but with both of them, I get, "[DBNETLIB][ConnectionOpen (Connect()).]Specified SQL server not found."
What values are needed?
The instance is not the database in the server you are connecting to. You can actually have more than one Sql Server running in the same operating system. You're using the default instance, so don't use that field or leave it blank.
Host: PlatypusSQL42
Username: youinnocentdog
Password:contrasena

How to connect to simple database table?

I don't know much about databases - Sorry if the question seems silly.
I have sql server 2012 on my machine and i create simple database table.
I want to connect to this database table thru C# code.
So, I need to know my ConnectionString.
I don't understand the parameters of the ConnectionString.
I try to google it - but still didn't find any good explanation.
Anyone can please explain the connectionString fields ?
How to define the connectionString that i will be able to connect the local database ?
thanks
Your connection string should be as simple as like below
Data Source=.;Initial Catalog=DB_NAME;Integrated Security=True"
Where
Data Source=. means local database
Initial Catalog=DB_NAME means the database it will connect to
Integrated Security=True means it will use windows authentication (no user name and password needed; it will use logged in credential)
Take a look Here
(OR)
Search in Google with key term sqlconncectionstring which will fetch you many help.
EDIT:
You are getting exception cause Initial Catalog=DB_Name\Table_001. It should be Initial Catalog=DB_Name (only database name). Provide the table name in sql query to execute. Check some online tutorial to get more idea on the same.
You use . in data source only when you are connecting to local machine database and to the default SQL Server instance. Else if you are using different server and named SQL Server instance then your connection string should look like
using(SqlConnection sqlConnection = new SqlConnection())
{
sqlConnection.ConnectionString =
#"Data Source=Actual_server_name\actual_sqlserver_instance_name;
Initial Catalog=actual_database_name_Name;
Integrated Security=True;";
sqlConnection.Open();
}
In case you are using local machine but named SQL Server instance then use
Data Source=.\actual_sqlserver_instance_name;
Initial Catalog=Actual_Database_NAME;Integrated Security=True"
using System.Data.SqlClient;
Then create a SqlConnection and specifying the connection string.
SqlConnection myConnection = new SqlConnection("user id=username;" +
"password=password;server=serverurl;" +
"Trusted_Connection=yes;" +
"database=database; " +
"connection timeout=30");
Note: line break in connection string is for formatting purposes only
SqlConnection.ConnectionString
The connection string is simply a compilation of options and values to specify how and what to connect to. Upon investigating the Visual Studio .NET help files I discovered that several fields had multiple names that worked the same, like Password and Pwd work interchangeably.
User ID
The User ID is used when you are using SQL Authentication. In my experience this is ignored when using a Trusted_Connection, or Windows Authentication. If the username is associated with a password Password or Pwd will be used.
"user id=userid;"
Password or Pwd
The password field is to be used with the User ID, it just wouldn't make sense to log in without a username, just a password. Both Password and Pwd are completely interchangeable.
"Password=validpassword;"-or-
"Pwd=validpassword;"
Data Source or Server or Address or Addr or Network Address
Upon looking in the MSDN documentation I found that there are several ways to specify the network address. The documentation mentions no differences between them and they appear to be interchangeable. The address is an valid network address, for brevity I am only using the localhost address in the examples.
"Data Source=localhost;"
-or-
"Server=localhost;"
-or-
"Address=localhost;"-or-"Addr=localhost;"
-or-"Network Address=localhost;"
Integrated Sercurity or Trusted_Connection
Integrated Security and Trusted_Connection are used to specify wheter the connnection is secure, such as Windows Authentication or SSPI. The recognized values are true, false, and sspi. According to the MSDN documentation sspi is equivalent to true. Note: I do not know how SSPI works, or affects the connection.
Connect Timeout or Connection Timeout
These specify the time, in seconds, to wait for the server to respond before generating an error. The default value is 15 (seconds).
"Connect Timeout=10;"-or-
"Connection Timeout=10;"
Initial Catalog or Database
Initial Catalog and Database are simply two ways of selecting the database associated with the connection.
"Inital Catalog=main;"
-or-
"Database=main;"

How do I setup OLEDB to connect to a remote database?

I am locally running an Oracle 11g database. I have a small program connecting to it in code via OLEDB in VC++ (It only runs some database tests, I'm making sure I have all the basics down before I go into the real thing.) The connection information in code only includes the provider, instance name, user name, and password. All this aspect works fine.
//For example, both these ways of connecting work:
result = dataSource.Open(DATABASE_PROVIDER, DATABASE_NAME,
DATABASE_USER_NAME, DATABASE_USER_PASSWORD);
result = dataSource.OpenFromInitializationString(L"Provider=OraOLEDB.OracleDataSource=orcl;User ID=SYSTEM;Password=admin;");
I now want to send this program to other computers in my network and run it from there, connecting to my database on my local machine.
How would I go about connecting the other computers to my database in a way that the code will understand?
I have been trying to connect locally via IP instead of "localhost", figuring I could then simply use the same code and client. In that regard, I have tried a few things without success:
-I have tried modifying the connection string to change "Data Source" to my IP, but it could not connect.
-I have tried adding some parameters from other connection string examples I had seen, but they were not for Oracle and were ignored.
-I have also tried modifying tnsnames.ora and listener.ora to change local host to an IP address, but I know that didn't work, as it would still connect if I entered rubbish.
Anyone has the knowledge to help out?
For an Oracle db, you should set up a new tnsnames entry on their individual machines that points to your local db. Then use that new tns name as the datasource. You'll also need to make sure that your local db instance is accessible to them in the first place. (This is not enabled by default in Oracle Express, by the way.)
I've also generally had more success using msdaora as the data provider instead of OraOLEDB.

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