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.
If you’re getting an error that reads something like “Cannot DROP SEQUENCE ‘Sequence2’ because it is being referenced by object ‘DF__Dogs__DogId__6C190EBB’“, it could be because you’re trying to drop a sequence object that’s referenced by a DEFAULT constraint.
Sequences that are referenced by a DEFAULT constraint can’t be dropped until the DEFAULT constraint is dropped.
Therefore, to fix this issue, drop the DEFAULT constraint first.
Below are seven functions we can use to extract the hours, minutes, seconds, and microseconds from a time value in MySQL.
Continue readingIn 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.
By default, SQL Server sets its own minimum and maximum values for sequence objects based on the data type of the sequence object. Assuming we don’t set the data type for the sequence, these min/max values are based on the bigint data type (because that’s the default data type for sequence objects in SQL Server).
However, we can also set our own minimum and maximum values for our sequences. We can do this either explicitly (by setting the MAXVALUE and MINVALUE properties) or implicitly (by setting the data type).
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.
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.
If you’re getting error msg 6825 that reads “ELEMENTS option is only allowed in RAW, AUTO, and PATH modes of FOR XML“, it’s probably because you’re trying to use the ELEMENTS directive while using EXPLICIT mode of the FOR XML clause.
As the message alludes to, this option is not available when using the EXPLICIT mode (it’s only allowed with the RAW, AUTO, and PATH modes).
However, SQL Server does provide us with an equivalent that provides the same result. When using EXPLICIT mode, we can use the ELEMENT directive instead. We apply this to the column names, instead of the end of the query. We can alternatively use the ELEMENTXSINIL directive to ensure that elements are generated even if the column contains a NULL value.
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.
If you’re getting an error that reads “Argument ‘AS’ cannot be used in an ALTER SEQUENCE statement.” in SQL Server, it’s probably because you’re trying to change the data type of a sequence object.
We can’t actually change the data type of a sequence object, so this error is to be expected.
If you need to change the data type of a sequence object, you’ll need to drop the sequence and recreate it with the correct data type.
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