In MongoDB, the $unionWith aggregation pipeline stage performs a union of two collections, and it includes duplicates.
This behaves in a similar way to SQL’s UNION ALL, which also includes duplicates. By contrast, using just UNION (i.e. without the ALL)in SQL removes duplicates.
In MongoDB, we don’t have the option of specifying $unionWith ALL or similar, so we need to reduce duplicates in another way.
In MongoDB, we can remove duplicates by using the $group stage.
You can use the SWITCHOFFSET() function in SQL Server to change the time zone offset on a datetimeoffset value.
The function accepts two arguments; a datetimeoffset(n) value (or an expression that can be resolved to a datetimeoffset(n) value), and the new time zone.
If you need to return a small sample of random documents from a collection, here are three approaches you can try using the aggregation pipeline.
If you’re trying to run a multi-line query in SQLcl or SQL*Plus, and you keep getting an error such as “Unknown Command”, but running it in SQL Developer causes no such error, maybe this post will help.
By default, SQLcl and SQL*Plus don’t allow blank lines in SQL statements. However, you can change this with the SET SQLBLANKLINES command.
Below are 4 functions that enable you to return the hour from a time value in MariaDB.
In SQL Server, the REPLACE() function enables us to replace a string with another string. But what if you want to replace a list of characters with another list of characters?
The TRANSLATE() function might help.
If you have a hidden index in MongoDB, you can use the unhideIndex() method or the collMod administration command to unhide it.
MariaDB has quite a number of functions that return the day from a date. It all depends on how you want to do it, and what you mean by “day”.
MariaDB needs to know whether you want the day name, the day of the week number, the day of the month, day of year, etc.
Below are 8 functions that enable you to return the day from a date in MariaDB, in its various forms.
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.