How do DATETIME values work in SQLite? - sqlite

Question

I’m creating Android apps and need to save date/time of the creation record. The SQLite docs say, however, "SQLite does not have a storage class set aside for storing dates and/or times" and it's "capable of storing dates and times as TEXT, REAL, or INTEGER values".
Is there a technical reason to use one type over another? And can a single column store dates in any of the three formats from row to row?
I will need to compare dates later. For instance, in my apps I will show all records that are created between date A until date B. I am worried that not having a true DATETIME column could make comparisons difficult.

Answer 1

SQlite does not have a specific datetime type. You can use TEXT, REAL or INTEGER types, whichever suits your needs.
Straight from the DOCS
SQLite does not have a storage class set aside for storing dates and/or times. Instead, the built-in Date And Time Functions of SQLite are capable of storing dates and times as TEXT, REAL, or INTEGER values:
TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS").
REAL as Julian day numbers, the number of days since noon in Greenwich on November 24, 4714 B.C. according to the proleptic Gregorian calendar.
INTEGER as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.
Applications can chose to store dates and times in any of these formats and freely convert between formats using the built-in date and time functions.
SQLite built-in Date and Time functions can be found here.

Answer 2

One of the powerful features of SQLite is allowing you to choose the storage type. Advantages/disadvantages of each of the three different possibilites:
ISO8601 string
String comparison gives valid results
Stores fraction seconds, up to three decimal digits
Needs more storage space
You will directly see its value when using a database browser
Need for parsing for other uses
"default current_timestamp" column modifier will store using this format
Real number
High precision regarding fraction seconds
Longest time range
Integer number
Lowest storage space
Quick operations
Small time range
Possible year 2038 problem
If you need to compare different types or export to an external application, you're free to use SQLite's own datetime conversion functions as needed.

Answer 3

SQLite does not have a storage class set aside for storing dates
and/or times. Instead, the built-in Date And Time Functions of SQLite
are capable of storing dates and times as TEXT, REAL, or INTEGER
values:
TEXT as ISO8601 strings ("YYYY-MM-DD HH:MM:SS.SSS"). REAL as Julian
day numbers, the number of days since noon in Greenwich on November
24, 4714 B.C. according to the proleptic Gregorian calendar. INTEGER
as Unix Time, the number of seconds since 1970-01-01 00:00:00 UTC.
Applications can chose to store dates and times in any of these
formats and freely convert between formats using the built-in date and
time functions.
Having said that, I would use INTEGER and store seconds since Unix epoch (1970-01-01 00:00:00 UTC).

Answer 4

For practically all date and time matters I prefer to simplify things, very, very simple... Down to seconds stored in integers.
Integers will always be supported as integers in databases, flat files, etc. You do a little math and cast it into another type and you can format the date anyway you want.
Doing it this way, you don't have to worry when [insert current favorite database here] is replaced with [future favorite database] which coincidentally didn't use the date format you chose today.
It's just a little math overhead (eg. methods--takes two seconds, I'll post a gist if necessary) and simplifies things for a lot of operations regarding date/time later.

Answer 5

Store it in a field of type long. See Date.getTime() and new Date(long)