---
title: "CASE Vs UNION Which is Better in SQL"
description: "How to choose either UNION or CASE in the SQL query is best explained."
url: https://srinimf.com/2017/10/21/sql-query-with-case-logic-avoid-union-why/
date: 2017-10-21
modified: 2026-10-25
author: "Srini"
image: https://i0.wp.com/srinimf.com/wp-content/uploads/2017/10/pexels-photo-3764402.jpeg?fit=1871%2C1300&ssl=1
categories: ["DB2", "SQL"]
tags: ["CASE instead of UNION", "DB2 Tips and Solutions", "SQL case w3schools"]
type: post
lang: en
---

# CASE Vs UNION Which is Better in SQL

Here is an example of SQL CASE and SQL Union. Here it shows [which is better](https://srinimf.com/2015/01/25/cobol-static-call-and-dynamic-call/). Click here for SQL Tips and Tricks

## SQL Union

Below is the SQL query used by UNION. The example adopted from [Craig Mullin’s blog](http://www.craigsmullins.com)

```
SELECT CREATOR, NAME, 'TABLE'FROM SYSIBM.SYSTABLESWHERE TYPE = 'T'UNIONSELECT CREATOR, NAME, 'VIEW 'FROM SYSIBM.SYSTABLESWHERE TYPE = 'V'UNIONSELECT CREATOR, NAME, 'ALIAS'FROM SYSIBM.SYSTABLESWHERE TYPE = 'A'ORDER BY NAME;
```

In the above case, the lines of SQL are more, and it takes a lot of time to process it. So, whenever you want to use multiple UNION statements, it is always better to use a CASE statement. Let me share an example of how it can be re-write using CASE.

Related[DB2 Tough Questions (1 of 4)](https://srinimf.com/2012/01/19/db2-tough-questions-1-of-4/)

## SQL Case

```
SELECT CREATOR, NAME,CASE TYPEWHEN 'T' THEN 'TABLE'WHEN 'V' THEN 'VIEW 'WHEN 'A' THEN 'ALIAS'ENDFROM SYSIBM.SYSTABLESORDER BY NAME;
```

Related Posts

- [How to Improve Your SQL Queries](https://srinimf.com/2015/02/05/db2-how-to-write-best-sql-queries/)DateFebruary 5, 2015
- [Grouping Sets: How to Simplify SQL Query](https://srinimf.com/2015/05/27/reduce-sql-complexity-with-grouping-sets-in-db2-v11/)DateMay 27, 2015
- [DB2: How to Use Set Operators Example SQL](https://srinimf.com/2017/12/13/db2-set-operators-to-never-miss-these/)DateDecember 13, 2017

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