Database Management Systems
SQLcl and SQL*Plus are command line interfaces for working with Oracle Database.
By default, they return an empty string whenever null occurs as a result of a SQL SELECT statement.
However, you can use SET NULL to specify a different string to be returned. Here I specified that the string null should be returned.
Starting with SQLcl version 21.2, we can now configure SQLcl for syntax highlighting.
That means that the code you write in SQLcl can be color coded, based on the syntax highlighting rules you apply.
When using SQLcl (Oracle’s command line interface), you can create a login.sql file, and have it run each time you run SQLcl.
This allows you to have commands executed each time you run SQLcl. For example, you can specify your formatting preferences in the login.sql file, set up aliases, etc.
Here I show you how to create a login.sql file and how to make it run each time you run SQLcl.
In Oracle, the ASIN() function returns the arcsine (inverse sine) of its argument.
In other words, it returns the value whose sine is the argument.
When you run a query against an Oracle database using SQLcl or SQL*Plus, the results are displayed according to the SQLFORMAT option. But within that, there are other things you can do to customise the format of the results.
One of the things you can do is specify a column separator for the output grid.
In MariaDB, JSON_VALID() is a built-in function that allows you to check whether or not a value is a valid JSON document.
You pass the value as an argument, and JSON_VALID() returns 1 if it’s a valid JSON document, and 0 if not.
In Oracle, the ACOS() function returns the arccosine (inverse cosine) of its argument.
In other words, it returns the value whose cosine is the argument.
In Oracle, the ABS() function returns the absolute value of its argument.
The absolute value is the non-negative value of a real number without regard to its sign. It describes the distance from zero that a number is on the number line, without considering direction.
In MariaDB, JSON_UNQUOTE() is a built-in function that removes quotes from a JSON value. In other words, it “unquotes” a JSON value.
In MariaDB, JSON_TYPE() is a built-in function that returns the type of a JSON value, as a string.