In Oracle Database, the USER function returns the name of the session user (the user who logged on).
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SYS_GUID() Function in Oracle
In Oracle Database, the SYS_GUID() function generates and returns a globally unique identifier (RAW value) made up of 16 bytes.
On most platforms, the generated identifier consists of a host identifier, a process or thread identifier of the process or thread invoking the function, and a nonrepeating value (sequence of bytes) for that process or thread.
NULLIF() Function in Oracle
In Oracle Database, the NULLIF() function compares two expressions, and returns null if both expressions are equal. If they are not equal, then the function returns the first expression.
NVL() Function in Oracle
In Oracle Database, the NVL() function allows us to replace null values with another value.
MariaDB Composite Date & Time Units Explained
MariaDB includes a bunch of date and time units that you can use when working with date and time values. For example, MONTH is a unit, and HOUR is another unit.
Some units are composite units. Composite units are when two units get combined into one. The naming convention is that each unit name is separated by an underscore. For example, MINUTE_SECOND is for minutes and seconds.
Below are some examples that demonstrate how composite units work in MariaDB.
COALESCE() Function in Oracle
In Oracle Database, the COALESCE() function returns the first non-null expression the expression list.
ROWIDTONCHAR() Function in Oracle
In Oracle Database, the ROWIDTONCHAR() function converts a ROWID value to NVARCHAR2 data type
It’s similar to the ROWIDTOCHAR() function, except that ROWIDTOCHAR() converts a ROWID value to VARCHAR2 data type.
ROWIDTOCHAR() Function in Oracle
In Oracle Database, the ROWIDTOCHAR() function converts a ROWID value to VARCHAR2 data type.
CHARTOROWID() Function in Oracle
In Oracle Database, the CHARTOROWID() function converts a string value to ROWID data type.