I have a sqlite table with a number of dates. I would like to execute a query to select those records where the Date is the previous date. I have tried the following but it doesn't work:
SELECT SUM(Amount) AS TOTAL FROM (SpentAmount) Where Date ='\(Date().yesterday)'"
and output is : '2018-07-02 05:43:16 +0000'
But I want only date and this format: '02-07-2018'.
And I m trying This : SELECT SUM(Amount) AS TOTAL FROM SpentAmount WHERE Date = DATE('now', '-1 days');
but this Query give me no result
This is my database Database
but when i execute the query then give me this result
If you want to target yesterday (i.e. the date before today), then use DATE('now', '-1 days'):
SELECT SUM(Amount) AS TOTAL
FROM SpentAmount
WHERE Date = STRFTIME('%d.%m.%Y', DATE('now', '-1 days'));
As a general comment, your current date format is very non ideal. It will be very hard to sort your table by date. Instead, you should always store your date information in ISO format with SQLite, i.e. use 2018-07-02, not 02-07-2018.
I want to get the day of the month from a datetime column in my Sqlite database. I could use simply
select strftime('%d',myColumn) from myTable
But the values are stored in UTC in the database and i want to get the dates based on the localtime. So i can do the below to get the localtime.
select date(myColumn, 'localtime') from myTable
Now how do i do both these operations together? The only way i can think is by doing inner query with the date() and outer query with strftime(). Is there another way?
The documentation says that modifiers like localtime are used with all date and time functions:
SELECT strftime('%d', myColumn, 'localtime') FROM myTable
I have a sqlite (v3) table with this column definition:
"timestamp" DATETIME DEFAULT CURRENT_TIMESTAMP
The server that this database lives on is in the CST time zone. When I insert into my table without including the timestamp column, sqlite automatically populates that field with the current timestamp in GMT, not CST.
Is there a way to modify my insert statement to force the stored timestamp to be in CST? On the other hand, it is probably better to store it in GMT (in case the database gets moved to a different timezone, for example), so is there a way I can modify my select SQL to convert the stored timestamp to CST when I extract it from the table?
I found on the sqlite documentation (https://www.sqlite.org/lang_datefunc.html) this text:
Compute the date and time given a unix
timestamp 1092941466, and compensate
for your local timezone.
SELECT datetime(1092941466, 'unixepoch', 'localtime');
That didn't look like it fit my needs, so I tried changing the "datetime" function around a bit, and wound up with this:
select datetime(timestamp, 'localtime')
That seems to work - is that the correct way to convert for your timezone, or is there a better way to do this?
simply use local time as the default:
CREATE TABLE whatever(
....
timestamp DATE DEFAULT (datetime('now','localtime')),
...
);
You should, as a rule, leave timestamps in the database in GMT, and only convert them to/from local time on input/output, when you can convert them to the user's (not server's) local timestamp.
It would be nice if you could do the following:
SELECT DATETIME(col, 'PDT')
...to output the timestamp for a user on Pacific Daylight Time. Unfortunately, that doesn't work. According to this SQLite tutorial, however (scroll down to "Other Date and Time Commands"), you can ask for the time, and then apply an offset (in hours) at the same time. So, if you do know the user's timezone offset, you're good.
Doesn't deal with daylight saving rules, though...
In the (admitted rare) case that a local datatime is wanted (I, for example, store local time in one of my database since all I care is what time in the day is was and I don't keep track of where I was in term of time zones...), you can define the column as
"timestamp" TEXT DEFAULT (strftime('%Y-%m-%dT%H:%M','now', 'localtime'))
The %Y-%m-%dT%H:%M part is of course optional; it is just how I like my time to be stored. [Also, if my impression is correct, there is no "DATETIME" datatype in sqlite, so it does not really matter whether TEXT or DATETIME is used as data type in column declaration.]
When having a column defined with "NOT NULL DEFAULT CURRENT_TIMESTAMP," inserted records will always get set with UTC/GMT time.
Here's what I did to avoid having to include the time in my INSERT/UPDATE statements:
--Create a table having a CURRENT_TIMESTAMP:
CREATE TABLE FOOBAR (
RECORD_NO INTEGER NOT NULL,
TO_STORE INTEGER,
UPC CHAR(30),
QTY DECIMAL(15,4),
EID CHAR(16),
RECORD_TIME NOT NULL DEFAULT CURRENT_TIMESTAMP)
--Create before update and after insert triggers:
CREATE TRIGGER UPDATE_FOOBAR BEFORE UPDATE ON FOOBAR
BEGIN
UPDATE FOOBAR SET record_time = datetime('now', 'localtime')
WHERE rowid = new.rowid;
END
CREATE TRIGGER INSERT_FOOBAR AFTER INSERT ON FOOBAR
BEGIN
UPDATE FOOBAR SET record_time = datetime('now', 'localtime')
WHERE rowid = new.rowid;
END
Test to see if it works...
--INSERT a couple records into the table:
INSERT INTO foobar (RECORD_NO, TO_STORE, UPC, PRICE, EID)
VALUES (0, 1, 'xyz1', 31, '777')
INSERT INTO foobar (RECORD_NO, TO_STORE, UPC, PRICE, EID)
VALUES (1, 1, 'xyz2', 32, '777')
--UPDATE one of the records:
UPDATE foobar SET price = 29 WHERE upc = 'xyz2'
--Check the results:
SELECT * FROM foobar
Hope that helps.
SELECT datetime(CURRENT_TIMESTAMP, 'localtime')
SELECT datetime('now', 'localtime');
Time ( 'now', 'localtime' ) and Date ( 'now', 'localtime' ) works.
You can also just convert the time column to a timestamp by using strftime():
SELECT strftime('%s', timestamp) as timestamp FROM ... ;
Gives you:
1454521888
'timestamp' table column can be a text field even, using the current_timestamp as DEFAULT.
Without strftime:
SELECT timestamp FROM ... ;
Gives you:
2016-02-03 17:51:28
I think this might help.
SELECT datetime(strftime('%s','now'), 'unixepoch', 'localtime');
The current time, in your machine's timezone:
select time(time(), 'localtime');
As per http://www.sqlite.org/lang_datefunc.html
I have a SQLite database where I store the dates as ticks. I am not using the default ISO8601 format. Let's say I have a table defined as follows:
CREATE TABLE TestDate (LastModifiedTime DATETIME)
Using SQL, I wish to insert the current date and time. If I execute any of the below statements, I end up getting the date and time stored as a string and not in ticks.
INSERT INTO TestDate (LastModifiedTime) VALUES(CURRENT_TIMESTAMP)
INSERT INTO TestDate (LastModifiedTime) VALUES(DateTime('now'))
I have looked at the SQLite documenation, but I do not seem to find any option to obtain the current timestamp in ticks.
I can of course define a parameter in C# and store the value as a System.DateTime. This does result in the datetime getting stored to the database in ticks.
What I would like to do is be able to insert and update the current timestamp directly from within the SQL statement. How would I do this?
Edit:
The reason I want the data stored as ticks in the database, is that the dates are stored in the same format as stored by the ADO.Net data provider, and so that when the data is also queried using the ADO.Net provider it is correctly retrieved as a System.DataTime .Net type.
This particular oddity of SQLite caused me much anguish.
Easy way - store and retrieve as regular timestamp
create table TestDate (
LastModifiedTime datetime
);
insert into TestDate (LastModifiedTime) values (datetime('now'));
select datetime(LastModifiedTime), strftime('%s.%f', LastModifiedTime) from TestDate;
Output: 2011-05-10 21:34:46|1305063286.46.000
Painful way - store and retrieve as a UNIX timestamp
You can use strftime to retrieve the value in ticks. Additionally, to store a UNIX timestamp (roughly equivalent to ticks), you can can surround the number of seconds in single-quotes.
insert into TestDate (LastModifiedTime) values ('1305061354');
SQLite will store this internally as some other value that is not a UNIX timestamp. On retrieval, you need to explicitly tell SQLite to retrieve it as a UNIX timestamp.
select datetime(LastModifiedTime, 'unixepoch') FROM TestDate;
To store the current date and time, use strftime('%s', 'now').
insert into TestDate (LastModifiedTime) VALUES (strftime('%s', 'now'));
Full example:
create table TestDate (
LastModifiedTime datetime
);
insert into TestDate (LastModifiedTime) values (strftime('%s', 'now'));
select datetime(LastModifiedTime, 'unixepoch') from TestDate;
When executed by sqlite3, this script with print:
2011-05-10 21:02:34 (or your current time)
After further study of the SQLite documentation and other information found on date number conversions, I have come up with the following formula, which appears to produce correct results:
INSERT INTO TestDate(LastModifiedTime)
VALUES(CAST((((JulianDay('now', 'localtime') - 2440587.5)*86400.0) + 62135596800) * 10000000 AS BIGINT))
Seems like a painful way to produce something that I would expect to be available as a built-in datetime format, especially that the database supports the storing of datetime values in ticks. Hopefully, this becomes useful for others too.
Update:
The above formula is not perfect when it comes to daylight savings. See section Caveats And Bugs in SQLite docs regarding local time calculation.
The following will return the number of milliseconds since the UNIX Epoch:
SELECT (strftime('%s', 'now') - strftime('%S', 'now') + strftime('%f', 'now')) * 1000 AS ticks
It works by grabbing the number of seconds since the Unix Epoch (%s), subtracting the number of seconds in the current time (%S), adding the number of seconds with decimal places (%f), and multiplying the result by 1000 to convert from seconds to milliseconds.
The subtraction and addition are to add precision to the value without skewing the result. As stated in the SQLite Documentation, all uses of 'now' within the same step will return the same value.
How do you obtain the current timestamp in Sqlite? current_time, current_date, current_timestamp both return formatted dates, instead of a long.
sqlite> insert into events (timestamp) values (current_timestamp);
sqlite> insert into events (timestamp) values (current_date);
sqlite> insert into events (timestamp) values (current_time);
sqlite> select * from events;
1|2010-09-11 23:18:38
2|2010-09-11
3|23:18:51
What I want:
4|23234232
The docs mention this method:
SELECT strftime('%s', 'now');
1284248196
And this one which includes the fractional part:
SELECT (julianday('now') - 2440587.5) * 86400.0;
1284248196.65098
Both represent Unix Time, the number of seconds passed since January 1, 1970.
SQLite now has unixepoch function that returns a unix timestamp (https://www.sqlite.org/lang_datefunc.html)
However right now I don't recommend it because some things like Sqlitebrowser and Entity Framework (6.0.8) don't seem to support it yet. Right now it's still better to use old strftime from accepted answer
select strftime('%W'),date('now'),date(),datetime(),strftime('%s', 'now');
result in
strftime('%W') - date('now') - date() - datetime() - strftime('%s', 'now')
08 - 2021-02-23 - 2021-02-23 - 2021-02-23 15:35:12- 1614094512