![]() Sqlite> insert into x values (strftime('%d/%m/%Y %H:%M:%S')) Sqlite> create table x(updatedtimestamp) Use ".open FILENAME" to reopen on a persistent database. Substr(UpdatedTimestamp,7,4) || '-' || substr(UpdatedTimestamp,4,2) || '-' || substr(UpdatedTimestamp,1,2) || substr(UpdatedTimestamp,11) SQLite version 3.34.0 11:31:14Ĭonnected to a transient in-memory database. So you need to "fix" your UpdatedTimestamp to the correct ordering and separators. SQLite3 uses a subset of ISO8601 so the format is YYYY-MM-DD HH:MM:SS If you change the ordering, then you cannot sort or compare (well, you can still do an equality compare, but not an ordering compare). In the datetime universe, the biggest thing is the year, then the month, then the day, then the hour, then the minute, then the second, then the various subparts of seconds. In order for such strings to sort (compare) properly they must be in big-endian order (biggest thing first, followed one after each by the next smaller thing). SQLite3 does not have a datetime data type - datetime data is stored as a text string. Where UpdatedTimestamp >= strftime('%d/%m/%Y %H:%M:%S', datetime('now', '-1 day'))Ĭan someone please point out where I'm going wrong here? Working within the confines of being limited on formatting data before it is inserted? (and also have a lot of historical data) For example, I've tried to convert datetime output into the same format to use for comparison, but this doesn't work. I'm also unable to order query output by date/time correctly. I'm unable to run a query that correctly selects all data from a specific date, or within a specific time period. The field the data is inserted into is a datetime data type. The format of the data I have is '%d/%m%Y %H:%M:%S' e.g. I have a table that I'm using to store datetime data. I've been struggling with a datetime problem on this database now for a couple of months and have yet to come up with a solution. I come from a background of Oracle and CA Ingres (remember that?!) databases and have recently started using sqlite3 for a small home project. Note that when sorting in descending order in SQLite, NULLs are displayed last.My first post here. Here's what the whole query should look like: To change the order to descending, use the DESC keyword after each column in the ORDER BY clause. This way, you can sort the rows in ascending order by date. You can use it when sorting the rows by date, that is, by year, numerical month, and day. This is how you convert a month name to a month number. After you finish converting all the values, remember to use the END keyword to close the CASE WHEN clause. Here, the column is exam_month, the current values in this column are ' January', ' February', …, ' December', and the new values are the numerical months 1, 2, …, 12. Then, after each WHEN, state the value in this column, use the THEN keyword, and specify the new value you'd like to assign instead of the old one. ![]() After the CASE keyword, specify the name of the column. You can convert month names to numerical months with a CASE WHEN clause. To sort the rows by exam date, you need to sort first by year, then by numerical month (not month name), and finally by day. ![]() The result looks like this (the rows are sorted in ascending order by exam_year, exam_month, and exam_day): subject The months are given in names, not in numbers. The exam table has the following columns: subject, exam_year, exam_month, and exam_day. Also, the rows with the same exam_date are displayed in random order (you may see Science second and Health third, or Health second and Science third). Note that in SQLite, NULLs are displayed first when sorting in ascending order and last when sorting in descending order. If you'd like to see the latest date first and the earliest date last, you need to sort in descending order. You could also use the ASC keyword to make it clear that the order is ascending (the earliest date is shown first, the latest date is shown last, etc.). This way, you'll sort the data in ascending order by this column. Use the ORDER BY keyword and the name of the column by which you want to sort. The result looks like this (the rows are sorted in ascending order by exam_date): Subject The exam table has two columns, subject and exam_date. ![]()
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