I want to retrieve a time from Mysql table and want to get it's difference with current time time.
To be More clear :
[Current_Time]-[Time retrieved from SQL TABLE] = HH:MM:SS
You can do the calculation in the database. For instance, if the "time column" is stored as datetime:
select timediff(now(), t.timecol)
from table
If the timecol is stored as a time data type, then use:
select timediff(curtime(), t.timecol)
from table
Related
My webhost server and its mysql database are not synced to the same time. I need the current timestamp from the mysql database. Right now, I have a table that I update a timestamp when I need to get the time. Is there a function that I can get the current timestamp from the mysql database without using a table?
I want to avoid having to store a timestamp, calling to update it and then selecting it everytime I need the current mysql database time.
Should be like this:
select now()
or
select current_timestamp
Plenty examples here
There exists 3 different functions which returns needed value.
See Date and Time Functions
NOW() Return the current date and time at which the SQL statement executes.
It have a lot of aliases: CURRENT_TIMESTAMP(), CURRENT_TIMESTAMP, LOCALTIME(), LOCALTIME, LOCALTIMESTAMP, LOCALTIMESTAMP().
SYSDATE() Return the current date and time at which the function itself executes.
UTC_TIMESTAMP() Return the current UTC date and time.
All 3 functions have optional argument - fractional part length specificator. Allowed values from 0 to 6 which means the accuracy from a second till a microsecond.
I am having`a whole mysql table of approx 40,000 rows with a column named 'epoch_time' and there is epoch time in it and I want to convert that whole table's 'epoch_time' to a equivalent 'date' together in a single sql query and I'm doing this is in php_my_admin . Thanks in advance.
I guess by epochtime you mean UNIX-style timestamps, that is, number of seconds since 1970-01-01T00:00Z. If my guess is wrong, so is the rest of my answer.
First you add a new column to the table.
ALTER TABLE mytable ADD COLUMN datestamp DATETIME AFTER epochtime;
This names the new column datestamp and puts it right after epochtime in the list of columns.
Then you update the whole table to populate the new column from the old using FROM_UNIXTIME(). Omitting the WHERE clause makes the update work on the whole table (careful!).
UPDATE mytable SET datestamp = FROM_UNIXTIME(epochtime);
Finally, if you wish you can drop the old column.
UPDATE TABLE mytable DROP COLUMN epochtime;
If I were you I'd try all this on a copy of your database to ensure it is correct before doing it on your production database.
If your epochtime values already have the TIMESTAMP data type, they are already stored internally as UTC (f/k/a GMT) times. The update operation I suggested will convert them to local time according to the settings on your server.
If your application has users in multiple time zones, you may wish to keep using the TIMESTAMP datatype: it honors time zone settings. If your epoch times are stored in an INT column, you can create your new column with the TIMESTAMP rather than DATETIME type by substituting this line for the first one in my instructions above.
ALTER TABLE mytable ADD COLUMN datestamp TIMESTAMP AFTER epochtime;
mysql - I have a table , a column of unix timestamps called time, which I have already changed to datetime format, but I can't select other columns of my table.
To change the unix timestamps I have used the following statement:
SELECT
from_unixtime (time)
FROM
calllog
and changed to datetime format successfully, but when I add other columns to the select query the result is 1 in all the time columns. What can be done?
I have a table that stores the date/time as a Unix timestamp.
Is it possible to query the table and pick out all the entries that are a Monday without having to query all the rows and process them outside of MySQL?
Thanks!
SELECT * FROM your_table WHERE DAYOFWEEK(FROM_UNIXTIME(your_unix_timestamp_column)) = 2
I got an existing Mysql table with one of the columns as time int(10)
The field has many records like
1455307434
1455307760
Is it a date time, encrypted.
What should be the select Query, so it should display an actual date.
FROM_UNIXTIME()
SELECT FROM_UNIXTIME(mycolumn)
FROM mytable