In MySQL, JSON_TABLE() is a built-in function that converts JSON data into a relational form.
In other words, it lets you return a JSON document as a table.
The JSON_TABLE() function was introduced in MySQL 8.0.
MySQL
How CAST() Works in MySQL
In MySQL, CAST() is a built in function that converts a value to another data type. It takes a value of one type and returns a value of the specified type.
You provide the value as an argument when you call the function, as well as the type that you’d like it converted to.
CAST() works similar to CONVERT(), except that the syntax used is slightly different.
Fix “ERROR 1298 (HY000): Unknown or incorrect time zone…” in MySQL
If you’re getting error 1298 that reads something like “ERROR 1298 (HY000): Unknown or incorrect time zone: ‘UTC’” in MySQL, it’s probably because you’re specifying a time zone name, but your MySQL installation hasn’t yet been configured for named time zones.
To fix this issue, be sure that your MySQL installation has been configured for named time zones.
How LAST_INSERT_ID() Works in MySQL
In MySQL, the LAST_INSERT_ID() function returns the first automatically generated value successfully inserted for an AUTO_INCREMENT column as a result of the most recently executed INSERT statement.
It can also be called with an argument, in which case, it returns the value of the expression and the next call to LAST_INSERT_ID() will return the same value.
7 Functions that Separate Hours, Minutes, Seconds, & Microseconds from a Time Value in MySQL
Below are seven functions we can use to extract the hours, minutes, seconds, and microseconds from a time value in MySQL.
MySQL ICU_VERSION() Explained
In MySQL, the ICU_VERSION() function returns the version of the International Components for Unicode (ICU) library used to support regular expression operations.
The ICU_VERSION() function is primarily intended for use in test cases.
How CURRENT_ROLE() Works in MySQL
In MySQL, CURRENT_ROLE() is a built-in function that returns the current active roles for the current session, separated by commas, or NONE if there are none. The current role determines our access privileges.
MySQL COERCIBILITY() Explained
In MySQL, the COERCIBILITY() returns the collation coercibility value of its string argument.
The COERCIBILITY() function defines how collations will be converted in the case of collation conflict. In such conflicts, an expression with a higher coercibility is converted to the collation of an expression with a lower coercibility.
How CONNECTION_ID() Works in MySQL
The MySQL CONNECTION_ID() function returns the connection ID (thread ID) for the connection.
In MySQL, every connection has an ID that is unique among the set of currently connected clients. We can use the CONNECTION_ID() function to return that ID.