Database Management Systems
When using JSON with SQL Server, you can use the JSON_QUERY() function to extract an object or an array from a JSON string.
To use this function, you provide the JSON expression as an argument. You can also provide a second (optional) argument to specify the object or array to extract.
When using JSON with SQL Server, you can use the JSON_VALUE() function to return a scalar value from a JSON string.
To use this function, you provide two arguments; the JSON expression, and the property to extract.
When using SQL Server, you can use the ISJSON() function to test whether or not a string expression contains valid JSON.
If the expression contains valid JSON, ISJSON() returns 1, otherwise it returns 0.
From SQL Server 2022, we also have the option of testing for a specific JSON type.
Continue readingWhen using SQL Server, you can use the FOR JSON clause in a query to format the results as JSON. When doing this, you must choose either the AUTO or the PATH option. This article contains examples of using the PATH option.
In SQL Server you can use the FOR JSON clause in a query to format the results as JSON. When doing this, you must choose either the AUTO or the PATH option. This article contains examples of using the AUTO option.
In MySQL, the ORD() function returns the numeric value of the leftmost character of a given string. You provide the string as an argument.
If the leftmost character is a multibyte character, the returned value is calculated from the numeric values of its constituent bytes. If the leftmost character is not a multibyte character, the return value is its ASCII code (which is the same result as when using the ASCII() function).
In MySQL, the ASCII() function returns the numeric ASCII code of the leftmost character of a given string. You provide the string as an argument.
This article contains examples of usage.
In MySQL, the YEARWEEK() function returns the year and week for a given date. You provide the date as an argument, and the function will return the result accordingly.
You also have the option of specifying whether to start the week on Sunday or Monday, and whether the week should be in the range 0 to 53 or 1 to 53.
In MySQL, you can use the WEEKOFYEAR() function to return the calendar week for a given date. Simply provide the date as an argument and the function will return the calendar week as a number in the range from 1 to 53.
In MySQL, you can use the WEEKDAY() function to return the weekday index for a given date. Simply provide the date as an argument and the function will return the weekday index.