Below are two methods for returning rows that only contain alphanumeric characters in Oracle Database.
Alphanumeric characters are alphabetic characters and numeric characters.
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4 Ways to List All Views in a MariaDB Database
Below are four ways to list out the views in a MariaDB database using SQL or the command line.
4 Ways to Check if a Table Exists Before Dropping it in SQL Server (T-SQL)
Dropping a table in SQL easy. You simply use DROP TABLE myTable where myTable is the name of the table you want to drop. You can use this method to drop a table in SQL Server via T-SQL script.
But you’ll get an error if the table doesn’t actually exist. That is, unless you check for the existence of the table first.
Below are four ways of using T-SQL to check whether the table exists before dropping it.
2 Ways to Delete Duplicate Rows in SQLite
The following options can be used to delete duplicate rows in SQLite.
These examples delete duplicate rows but keep one. So if there are three identical rows for example, it deletes two of them and keeps one. This is often referred to as de-duping the table.
Find Values That Don’t Contain Numbers in PostgreSQL
The following example returns all rows that don’t contain any numbers in PostgreSQL.
Numbers can be represented by words and other symbols, but for this article “number” simply means “numerical digit”. So we’re finding values that don’t contain any numerical digits.
4 Ways to Find Rows that Contain Uppercase Characters in PostgreSQL
Here are four options for returning rows that contain uppercase letters in PostgreSQL.
How to Format the Month in Roman Numerals in Oracle
Oracle Database provides us with the ability to return the month from a date using roman numerals.
For example, if the month is August, its decimal value would be 08 and it’s roman numeral equivalent would be VIII.
The way to do this is to use the RM or rm format element in your format mask. That will format the month using roman numerals in uppercase or lowercase respectively.
Specifying the date format can be done in several places.
4 Ways to Find Duplicate Rows in MySQL
If you think a MySQL table might have duplicate rows, you can use the following options to return all duplicates.