![]() Should any right be infringed, it is totally unintentional.ĭrop me an email and I will promptly and gladly rectify it. Registered trademarks of their respective companies. You select the table with ALTER TABLE tablename and then write which column to rename and what to rename it to with RENAME COLUMN oldname TO newname. Software and hardware names mentioned on this site are You can rename a column with the below code. No portion may be reproduced without my written permission. Using LIMIT Clause to Constrain the Number of Rows RetrievedĬopyright © 2023. Use WHERE Clause to Conditionally Select RowsĦ. Produced the same result whether single or double quotes are used.Ĥ. Literal strings are discussed in Using Literal Character Strings section. The second query uses single quotation marks to enclose column alias name - not recommend as single quotes are normally The first query uses double quotation marks to enclose column alias name. SELECT CategoryID AS ' Category ID ', CategoryName AS ' Category Name ' Use single quotes around column alias - Not recommended. SELECT CategoryID AS " Category ID ", CategoryName AS " Category Name " Practice #1: execute SELECT statement with or without using keyword AS before column alias name Most of the queries in the tutorials need Northwind MySQL database, you can download the database script on this page. JOINs are covered in Querying Multiple Tables section. This can happen when joining two or more tables and these tables may use the same column names. Use column alias when there is a column name conflict. The following SQL script will rename PinCode to ZipCode in the Employee table in Oracle, MySQL, PostgreSQL, SQLite database. Use column alias with single quotes (' ') or double quotes (" ") if you need to put spaces or add special characters (such as $, #, in the column heading. Syntax: ALTER TABLE tablename RENAME COLUMN oldcolumnname TO newcolumnname For the demo purpose, consider the following Employee table. ![]() For example, if the column name does not make too much business sense, you can use a meaningful alias instead. Use column alias if the original column name does not meet your requirements. Optionally, you can add the keyword AS in between the column name and the column alias to clearly indicate the use of alias. Read Prerequisites for this tutorial and practices if you haven't done so.Ĭonsider the following facts when using column alias:Ĭolumn alias is added in the SELECT statement immediately after the column name. ![]() That is, you can change a column heading by using By default, after executing a SELECT statement, the column heading(s) displayed in the result set is ![]()
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