SQL Archives | Official TuningSQL.com Blog
Skip to content
  • TuningSQL.com
  • TuningSQL.com
Official TuningSQL.com Blog

Official TuningSQL.com Blog

Oracle Database SQL, Tuning, Features, and Toubleshooting

Category: SQL

  • Home
  • Oracle
  • SQL

How to Fix “ORA-01489: Result of String Concatenation is Too Long” When Using Listagg

August 19, 2020November 16, 2020 Kaley Crum

If you’re using the LISTAGG() function in Oracle, and you’ve encountered the error ORA-01489: result of string concatenation is too long it’s because you’re trying to create a comma-delimited list that is too long for a VARCHAR2. In Oracle, a… Read More

Oracle, Oracle Error Messages, Problems and Troubleshooting, SQL2 Comments

ORA-12727: Invalid Back Reference In Regular Expression

August 17, 2020August 17, 2020 Kaley Crum

If you’ve run across ORA-12727: invalid back reference in regular expression, it’s because you’ve referenced a group (a group is an expression enclosed in parenthesis) either that doesn’t exist, or doesn’t exist yet. There are two common reasons for this… Read More

Oracle, Oracle Error Messages, Problems and Troubleshooting, Regular ExpressionsLeave a comment

Index Range Scan vs. Leading Wildcard

July 2, 2020August 13, 2020 Kaley Crum

Can you use an index range scan with a LIKE if you have a leading wildcard in your expression? e.g. Most people would say “no” but, I actually found a way to “trick” Oracle into doing so using bind variables,… Read More

Bind Variables, Execution Plans, OracleLeave a comment

Oracle: Coding Around NULL Values

June 18, 2020August 13, 2020 Kaley Crum

In Oracle, NULLs can complicate your code–a lot. Suppose, for example, you want to see if two different values are the same in a SQL query. You might be tempted to write something like this: The problem with the above… Read More

NULL Values, NULL Values, Oracle, Pl/SQL, SQLLeave a comment

Calculating Scalar Subquery Cache Size

February 28, 2020August 13, 2020 Kaley Crum

Whenever you have a scalar subquery in Oracle, there are a few different options that Oracle can use for executing the subquery. Oracle can either run the query once for each row returned by the records in the from clause.… Read More

Caching, Oracle, Scalar Subqueries, SQL, Tuning/Efficiency, Writing Queries for PerformanceLeave a comment

FREE Sql Tuning Tips!

Get FREE tips and tricks for FASTER Oracle SQL queries delivered directly to your email inbox!

Just a minute...

Awesome! You're subscribed!!

Recent Posts

  • Selecting From a View: ORA-01031: insufficient privileges
  • Calculating Scalar Subquery Cache Size, Part 2
  • How to Migrate a Baseline From One Database to Another
  • How to Get A Query’s Execution Plan (With All The Details)
  • Using DBMS_UTILITY.EXPAND_SQL_TEXT

Categories

  • Approximate Query Processing
  • Arrays
  • Autonomous
  • Baselines
  • Bind Variables
  • Caching
  • Certification
  • Creating Users
  • Cursors
  • Custom Aggregation
  • Data Dictionary Views
  • Data Types
  • Database Objects
  • Day to Second Interval
  • DBMS_METADATA
  • DBMS_UTILITY
  • Dirty Hacks
  • Execution Plans
  • Explain Plans
  • FORALL
  • Hash Clusters
  • Hash Joins
  • Hints
  • Keywords
  • Network Connections
  • NULL Values
  • NULL Values
  • Oracle
  • Oracle Error Messages
  • Oracle SQL Developer
  • Pl/SQL
  • Pl/SQL Compiler Flags
  • Pluggable Databases
  • Pragmas
  • Privileges
  • Problems and Troubleshooting
  • Regular Expressions
  • Row Level Security
  • Row Source Statistics
  • Scalar Subqueries
  • Scripts and Queries
  • SQL
  • SQL Monitor Reports
  • SQL Plan Management
  • Table Definition
  • Table Statistics
  • Tuning/Efficiency
  • User Profiles
  • Users
  • Version
  • Virtual Columns
  • Wrapping Pl/SQL Code
  • Writing Queries for Performance
Copyright © TuningSQL.com All rights reserved.
Business Cast by Axle Themes