SQLite Order By Date1530019888000

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?

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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.

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最佳答案

you can do it like this

SELECT * FROM Table ORDER BY date(dateColumn) DESC Limit 1
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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

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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
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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!

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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.

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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 ...

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You can also use the following query

"SELECT * FROM Table ORDER BY strftime('%Y-%m-%d %H:%M:%S'," + dateColumn + ") DESC  Limit 1"
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This will work for both date and time

SELECT *
FROM Table
ORDER BY
julianday(dateColumn)
DESC Limit 1
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I found this ugly hack worked.

select *, substr(date_col_name,7,4)as yy, substr(date_col_name,4,2) as mm, substr(date_col_name,1,2) as dd from my_table order by yy desc,mm desc,dd desc

it would be better to convert the text column to date field type, but I found that did not work reliably for me.


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