Every record in my SQLite
database contains a field which contains a Date
stored as a string
in the format 'yyyy-MM-dd HH:mm:ss'
.
Is it possible to query the database to get the record which contains the most recent date please?
you can do it like this
SELECT * FROM Table ORDER BY date(dateColumn) DESC Limit 1
For me I had my query this way to solve my problem
select * from Table order by datetime(datetimeColumn) DESC LIMIT 1
Since I was storing it as datetime not date column
You need to convert it to unix timestamp, and then compare them:
SELECT * FROM data ORDER BY strftime('%s', date_column) DESC
But this can be pretty slow, if there are lots of rows. Better approach would be to store unix timestamp by default, and create an index for that column.
When you sure the format of text field is yyyy-MM-dd HH:mm:ss
(ex.: 2017-01-02 16:02:55
), So It works for me simply:
SELECT * FROM Table ORDER BY dateColumn DESC Limit 1
Without any extra date function!
You can convert your column "sent_date_time" to yyyy-MM-dd format and then order by date
1 ) substr(sent_date_time,7,4)||"-"||substr(sent_date_time,1,2)||"-"||substr(sent_date_time,4,2) as date
2) order by date desc
In my case everything works fine without casting column to type 'date'. Just by specifying column name with double quotes like that:
SELECT * FROM 'Repair' ORDER BY "Date" DESC;
I think SQLite makes casting by itself or something like that, but when I tried to 'cast' Date column by myself it's not worked. And there was no error messages.
If you do a lot of date sorting/comparison, you may get better results by storing time as ticks rather than strings, here is showing how to get 'now' in ticks with:
((strftime('%s', 'now') - strftime('%S', 'now') + strftime('%f', 'now')) * 1000)
(see https://stackoverflow.com/a/20478329/460084)
Then it's easy to sort, compare, etc ...
来源:https://stackoverflow.com/questions/14091183/sqlite-order-by-date1530019888000