Syntax
------ 
SYSDATE([precision])
 
Description
----------- 
Returns the current date and time as a value in 'YYYY-MM-DD
HH:MM:SS'
or YYYYMMDDHHMMSS.uuuuuu format, depending on whether the
function is
used in a string or numeric context.
 
The optional precision determines the microsecond precision.
See Microseconds in MariaDB.
 
SYSDATE() returns the time at which it executes. This
differs from the
behavior for NOW(), which returns a constant time that
indicates the
time at which the statement began to execute. (Within a
stored routine
or trigger, NOW() returns the time at which the routine or
triggering
statement began to execute.)
 
In addition, changing the timestamp system variable with a
SET timestamp statement affects the value returned by
NOW() but not by SYSDATE(). This means that timestamp
settings in the
binary log have no effect on invocations of SYSDATE().
 
Because SYSDATE() can return different values even within
the same
statement, and is not affected by SET TIMESTAMP, it is
non-deterministic and therefore unsafe for replication if
statement-based binary logging is used. If that is a
problem, you can
use row-based logging, or start the server with the mysqld
option --sysdate-is-now to cause SYSDATE() to be an alias
for NOW(). The non-deterministic nature of SYSDATE() also
means that indexes cannot be used for evaluating expressions
that refer to it, and that statements using the SYSDATE()
function are unsafe for statement-based replication.
 
Examples
-------- 
Difference between NOW() and SYSDATE():
 
SELECT NOW(), SLEEP(2), NOW();
+---------------------+----------+---------------------+
| NOW() | SLEEP(2) | NOW() |
+---------------------+----------+---------------------+
| 2010-03-27 13:23:40 | 0 | 2010-03-27 13:23:40 |
+---------------------+----------+---------------------+
 
SELECT SYSDATE(), SLEEP(2), SYSDATE();
+---------------------+----------+---------------------+
| SYSDATE() | SLEEP(2) | SYSDATE() |
+---------------------+----------+---------------------+
| 2010-03-27 13:23:52 | 0 | 2010-03-27 13:23:54 |
+---------------------+----------+---------------------+
 
With precision:
 
SELECT SYSDATE(4);
+--------------------------+
| SYSDATE(4) |
+--------------------------+
| 2018-07-10 10:17:13.1689 |
+--------------------------+
 


URL: https://mariadb.com/kb/en/sysdate/