If you’re using a T-SQL function such as OPENJSON(), JSON_QUERY(), or JSON_VALUE(), you might be wary of any non-alphanumeric characters that might be in the JSON document that you’re working with. Especially if those special characters are in the key names, and you need to reference those key names.
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3 Ways to Hide an Index from the Query Plan in MongoDB
Starting from MongoDB 4.4, we can now hide indexes from the query plan. This enables us to evaluate the potential impact of dropping an index without actually dropping the index.
If hiding it has a negative impact, we can unhide the index. This saves us from having to drop the index, then recreate it again.
Below are 3 ways to hide an index in MongoDB.
3 Ways to Return Distinct Values in MongoDB
Distinct values are those values with redundant duplicates removed. In other words, distinct values are unique values.
In MongoDB there are a few ways we can return distinct values in a query. This article presents 3 ways to return distinct values in the mongo shell.
3 Ways to Drop an Index in MongoDB
MongoDB provides several ways to drop an index or indexes.
To drop a single index, you can use the dropIndex() method.
To drop multiple indexes, you can use either the dropIndexes() method or the dropIndexes administration command.
How to Set MariaDB to use Vertical Output
If you connect to MariaDB using the command line interface, you might sometimes find that your query results are too wide, due to the number of columns being returned, and the data they contain.
How to Truncate Text with an Ellipsis in MariaDB
Sometimes you might find that the amount of text returned in a database column is too long. You might just want to return a short snippet of that text, followed by an ellipsis or three dots.
Fortunately, this is relatively easy to do in MariaDB.
3 Ways to Show the Collation for your Connection in MariaDB
When you run a query against a MariaDB database, MariaDB uses a bunch of system variables to determine which character set and collation to use whenever queries are run. If the client uses a different character set to the server, then MariaDB can translate it into an appropriate character set and collation.
When sending the query results back to the client, MariaDB can translate these results back to a different character set altogether if required. MariaDB uses system variables to determine which character sets and collations to use at each of these steps.
Here are three ways to show the connection collation in MariaDB.
Convert a Month Number to the Month Name in SQL Server (T-SQL)
You can use the T-SQL code below to convert a month number to its corresponding name in SQL Server.
This is for times where you don’t actually have the full date – when all you have is the month number. If you do have the date, then here’s how to get the month name from a date.
Set the Character Set and Collation of a Database in MariaDB
You can specify the character set and collation at various levels in MariaDB. You can specify them at the connection level, the server level, the database level, the table level, and the column level.
You can also specify a collation in your queries so that it overrides any collation that has been previously specified at the aforementioned levels.
To set the character set and collation at the database level, use the CREATE DATABASE statement or ALTER DATABASE statement (depending on whether you’re creating the database or modifying it).