Java™ Application Development on Linux - Dator

324Chapter 14Storing the Data-bash-2.05b$ createuser mschwarzShall the new user be allowed to create databases? (y/n) yShall the new user be allowed to create more new users? (y/n) yCREATE USER-bash-2.05b$Here, we created the PostgreSQL user mschwarz and gave him the abilityto create databases and new users.14.9.3 Creating Our DatabaseNow that our username, mschwarz, has been created and is authorized to createdatabases, we use the createdb command to create our database:[mschwarz@cassidy mschwarz]$ createdb budgetProCREATE DATABASENotice that we did this as the Linux user mschwarz, so the createdbcommand used that username when it created the budgetPro database. Whatwould have happened if we had used a Linux user that did not have a matchingPostgreSQL user? Let’s see:[albing@cassidy albing]$ createdb budgetProcreatedb: could not connect to database template1: \FATAL: user "albing" does not existWARNINGNote that we have not implemented any security yet. The user mschwarz exists,but it does not have a password. Depending on how PostgreSQL securityis configured, it may be possible for any user to use the -U option with thePostgreSQL command-line utilities to impersonate mschwarz. As packagedfor Fedora Core 2, PostgreSQL uses ident to check authentication, so whenalbing attempts this, he gets this error:[albing@cassidy albing]$ createdb -U mschwarz budgetProcreatedb: could not connect to database template1: \FATAL: IDENT authentication failed for user "mschwarz"Just remember that this behavior is dependent on the local configurationof PostgreSQL. You cannot assume this security is in place just because youare in a PostgreSQL environment. Always be aware of the security configurationof your production environment!