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 →
Thumbnail image for UNPIVOT in Oracle 11G to Select Columns As Rows

UNPIVOT in Oracle 11G to Select Columns As Rows

You can easily transpose table columns to rows in Oracle 11G+ using the UNPIVOT clause is SQL. A comparison of the pre-11G DECODE solution with the 11G+ UNPIVOT method.

Read the Full Article →
Thumbnail image for SQL to Select Rows Conditionally Based On Column Value

SQL to Select Rows Conditionally Based On Column Value

SQL solution to select rows conditionally based on column value – for example, a priority column tagged to a set of rows, with a requirement to select only the rows with top priority.

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 →
Thumbnail image for I want to learn Oracle. Where should I begin?

I want to learn Oracle. Where should I begin?

Here is a simple guide to help you learn Oracle as a developer from scratch, on your own. Beginner-friendly Oracle Learning Library courses and free Oracle environments for hands-on practice.

Read the Full Article →
Thumbnail image for What are CBO and RBO?

What are CBO and RBO?

Oracle’s inbuilt optimizers – CBO and RBO: how they work to improve query performance, and key differences between cost-based vs rule-based optimization.

Read the Full Article →
Thumbnail image for UTL_HTTP to Call a Web Service from PL/SQL

UTL_HTTP to Call a Web Service from PL/SQL

You can call a web service from PL/SQL using the Oracle-supplied package UTL_HTTP. This article demos a PL/SQL script to invoke a web service and read its response into a CLOB. It also describes typical errors you may encounter in web service calls and how to resolve them.

Read the Full Article →
UTL_FILE: Simple write to file example

UTL_FILE: Simple Write To File Example and Debugging Common Errors

A simple example of using UTL_FILE in PLSQL to create a file and write into it. Plus, the common ORA errors you encounter with the use of UTL_FILE, and how to resolve them.

Read the Full Article →
SQL to Find Master Records with Identical Detail Records

SQL to Find Master Records with Identical Detail Records

The query to identify duplicate records in Oracle in a single table is fairly straightforward. Things get tricky in a two-table (master-detail) scenario, in which the master table holds the header information (id, name, etc) and the detail table has sets of values associated with the master records. What if we need to find those […]

Read the Full Article →