ORA Errors

Oracle database errors – probable causes, how to resolve them or work around them.

Thumbnail image for How to Lock a Row: SELECT FOR UPDATE

How to Lock a Row: SELECT FOR UPDATE

How to lock a row in Oracle and manage concurrency conflict during database transactions, with the use of the FOR UPDATE clause in SELECT statements.

Read the Full Article →
Thumbnail image for JSON Conditionals: JSON_EXISTS, JSON_TEXTCONTAINS

JSON Conditionals: JSON_EXISTS, JSON_TEXTCONTAINS

Implement true/false tests on JSON documents in Oracle database 12c using JSON conditional logic: JSON_EXISTS and JSON_TEXTCONTAINS.

Read the Full Article →
DBMS_REDEFINITION for online table redefinition

DBMS_REDEFINITION: Convert Non-Partitioned Table to Partitioned [pre 12.2]

Partitioning a non-partitioned table in an Oracle pre-12.2 database, using DBMS_REDEFINITION built-in methods. Scripts and demo.

Read the Full Article →
Thumbnail image for What are SQLCODE and SQLERRM?

What are SQLCODE and SQLERRM?

SQLCODE and SQLERRM are Oracle’s built-in error reporting functions in PL/SQL. See PL/SQL examples using SQLCODE and SQLERRM in various scenarios.

Read the Full Article →
Check if JVM is Installed in Oracle

How to Check if JVM is Installed in Oracle

Creating Java source in Oracle gives an ORA error? Check if JVM is installed and valid in the Oracle database, this way.

Read the Full Article →
Thumbnail image for DATE Format SQL for Dates Stored as Strings

DATE Format SQL for Dates Stored as Strings

Convert VARCHAR2 to DATE with appropriate format masks, for comparing two dates stored as strings with different DATE formats in the database.

Read the Full Article →
Thumbnail image for Grant SELECT on V$ Views

Grant SELECT on V$ Views

Grant SELECT on V$ views to allow non-admin database users to query SYS-owned V$ views (dynamic performance views) such as V$INSTANCE or V$SESSION.

Read the Full Article →
Thumbnail image for Access Control List (ACL) in Oracle 11G

Access Control List (ACL) in Oracle 11G

Access Control List or ACL is a security mechanism that defines which users or roles can perform which operations on which data. It is an essential setup in Oracle 11G for running network packages such as UTL_HTTP.

Read the Full Article →
TNS Protocol Adapter Error

ORA-12560: TNS:protocol adapter error

Sometimes you try to login to your Oracle XE and get a blocker ORA-12560 : TNS:protocol adapter error. Top reason why this error might occur and how to fix it.

Read the Full Article →
Thumbnail image for ORA-01450: Maximum Key Length Exceeded – Possible Causes and Fix

ORA-01450: Maximum Key Length Exceeded – Possible Causes and Fix

“ORA-01450 maximum key length (6398) exceeded” might occur when a table index is being created in the Oracle database. Possible reasons why this error shows up and how to fix it.

Read the Full Article →