All errors › ORA errors
ORA-12154: TNS: could not resolve the connect identifier specified
What it means
The client could not translate the alias in the connect string into an address: missing or wrong entry in tnsnames.ora, the client reads a different TNS_ADMIN, or a typo.
How to fix it
Use EZConnect (host:port/service_name) to skip tnsnames.ora, or check TNS_ADMIN and the alias. JDBC thin URLs use jdbc:oracle:thin:@//host:port/service.
Catch it before it runs
ORA Error Helper
Explains ORA-/PLS- codes inside JetBrains IDEs and DataGrip. PL/SQL Lint
Flags risky PL/SQL patterns while you type. Oracle Plan Reader
Reads execution plans and points at the slow step. PL/SQL in Practice
Kindle book with practical PL/SQL for working developers.
Explains ORA-/PLS- codes inside JetBrains IDEs and DataGrip. PL/SQL Lint
Flags risky PL/SQL patterns while you type. Oracle Plan Reader
Reads execution plans and points at the slow step. PL/SQL in Practice
Kindle book with practical PL/SQL for working developers.
Nearby errors
Updated 2026-11-12.