I have been searching for a setting in DB BRowser for SQLite on how to change the timezone to IST (Indian Standard Time +5:30) Is there a way to set it directly without running any queries? I also found some SQL queries that can convert the db time to IST but almost all are SELECT statements. I am looking for a setting to change the timezone permanently and if that is not possible then may be an update query which can read all records in the database and change/convert/replace all times to IST. Can someone shed some light on it?
My field name is "expire_time" set as DATETIME NOT NULL in CREATE TABLE
What I searched for was
INSERT INTO MyTable(MyColumn) VALUES(datetime(CURRENT_TIMESTAMP, 'localtime'))
but I am not looking for insert statement
SELECT datetime(1092941466, 'unixepoch', 'localtime');
but I am not looking for select statement
Please help me either with a setting (if available in DB Browser for SQLite) or an update query that can change all times from GMT TO IST.
Thanks.
EDIT
SQLite has no DATETIME type. And it treats datatypes very different from other DBMS. For example
CREATE TABLE T (
Field MYTYPE
);
will run OK. Sqlite is applying so called datatype affinity https://www.sqlite.org/datatype3.html#affinity to figure out one of the implemented datatypes it will use instead of stuff specified it CREATE TABLE. DATETIME (as well as MYTYPE) affinity is NUMERIC - a special affinity which means column can store any type you want, TEXT for example.
This boils down the only way to work with DATETIME in Sqlite is datetime functions. And those functions use default timezone UTC. Any other timezone must be provided explicitly as a part of the datetime string. No PRAGMA or something to change this default.
EDIT
If expire_time is currently a string expression of UTC time you can get specific timezone text value, for example
select datetime(expire_time, '+05 hours','+30 minutes') || ' IST' as t
Note datetime(d,'utc') will most probably return NULL if string d contains explicit timezone. So i advice you standardize on storing datetime as UTC in DB and convert it to different timezone needed only when generating an output. This way you have all Sqlite toolbelt at your disposal.
Related
Hi i want to change the default datetime type in sql server. I have already table who has rows and i dont want to delete them. Now the datetime format that had rows is: 2015-11-16 09:04:06.000 and i want to change in 16.11.2015 09:04:06 and every new row that i insert i want to take this datetime format.
SQL Server does not store DATETIME values in the way you're thinking it does. The value that you see is simply what the DBMS is choosing to render the data as. If you wish to change the display of the DATETIME type, you can use the FORMAT() built-in function in SQL Server 2012 or later versions, but keep in mind this is converting it to a VARCHAR
You can get the format you desire via the following:
SELECT FORMAT(YourDateField, N'dd.MM.yyyy HH:mm:ss')
There is no such thing as format of the DATETIME data type, it has no format by nature, formatted is the text representation you can set when converting to VARCHAR or some visualization settings of the client / IDE.
If you, however, want to be able to insert dates using string representations that are alternatively formatted (i.e. control the way string input is parsed to datetime type) you can check SET DATEFORMAT - as explained in the remarks section this will not change the display representation of date fields / variables.
SQL serve provide wide range of date formatting function or way by using that user can change date format as per his requirement.
Some of are giver bellow.
CONVERT(VARCHAR(19),GETDATE())
CONVERT(VARCHAR(10),GETDATE(),10)
CONVERT(VARCHAR(10),GETDATE(),110)
CONVERT(VARCHAR(11),GETDATE(),6)
CONVERT(VARCHAR(11),GETDATE(),106)
CONVERT(VARCHAR(24),GETDATE(),113)
How do you convert SQL mm/dd/yy datetime to mm/dd only? On Microsoft server.
Thanks all.
With dates and times it is an extremely common mistake to believe that what you see is what is stored. If the field is date, datetime, smalldatetime or datetime2 then what is stored are integers, not strings. So if the field is one of these, then:
convert(varchar(5),[date_field],1)
or
format([date_field],'MM/dd') -- mssql 2012 onward
If the information is a string already then left() will do the job.
Since you have specified an input format, the input must already be a string. Simply truncate with
cast(dateIn as char(5)).
You can use LEFT to just return the day and month:
SELECT LEFT('12/12/2000', 5)
I realize this isn't directly answering your question the way you asked it, but the best advice I can give is: Don't.
Instead, send back the field in its native datetime type. The database is not the place to be doing formatting. Instead, format the date in your application code.
For example, if you are calling SQL Server from a C#/.NET application, you could retrieve the value from a DataReader like this:
DateTime dt = (DateTime) reader["YourDateTime"];
Then you would format it as a string like this:
string s = dt.ToString("MM/dd");
This will ensure that the date is formatted correctly. If you are using a different language to call SQL Server, there are probably similar methods in that language.
One of the problems with the other approach mentioned (trunacating the string) is that the original value might not be formatted in mm/dd/yyyy to begin with. That all depends on the environment settings where the SQL Server is running. If you run the same code on an environment with dd/mm/yyyy settings, you would have unexpected results. This is avoided by using the native data type, the way I described.
I want to insert a datetime into a date field in oracle. I have up until now used sysdate, which works perfectly, however I need to use the same timestamp for something else.
Does anyone know how I can create a datetime variable that is compatible with oracle's date field? Everything I try causes errors.
I have tried variations along the lines of this:
Dim timestamp As DateTime = CDate(Now.ToString("yyyy/MM/dd HH:mm:ss"))
.......more code....
insertBuilder.Append("date = to_date(" & timestamp & ")")
First, you seem to be confused about the difference between a DateTime object and the formatted String representation of that DateTime object. Now, or even better, DateTime.Now is already a DateTime object, so it makes no sense to format it as a string and then parse the string to get it back into a DateTime value again. So, you can simply do this to accomplish the same thing:
Dim timestamp As Date = Date.Now
Note that in VB.NET, Date is a keyword that is short for DateTime, just as Integer is "short" for Int32.
Second, you should not be appending DateTime values directly into the SQL command string. You should be using a parameterized query. When you append the DateTime value to the SQL string, you must make sure it is formatted properly (by calling timestamp.ToString(...)). Unfortunately, however, which format is proper will depend entirely on the culture settings of the server. So, it is far better to use a DB parameter, set the parameter value equal to the actual DateTime object, and then let the DB provider do the conversion for you.
A parameterised query is a good start because you can pass a native .Net DateTime object into Enterprise Library (for example) and specify that it is of DbType.DateTime and let EL worry about it. However if you cannot do that because you aren't using EL or something similar and are stuck with using SQL strings as posted in your question then you need to be aware of how Oracle treats dates internally, particularly with regards to format.
Using SQL Developer or SQLPlus, execute the following:
Select To_Char(sysdate) from Dual;
The format which is displayed is the format which your Oracle instance expects dates to be in if you use To_Date and which Oracle will use in To_Char. If you deviate from that format in either call then you will get problems. However, regardless of the default format being used you can override it by specifying it in the call:
Select To_Char(sysdate, 'YYYY/MM/DD HH:MI:SS') from Dual;
Select To_Date('2013/02/26 05:03:27', 'YYYY/MM/DD HH:MI:SS') from Dual;
You can set the default you want Oracle to use implicitly by setting the NLS_DATE_FORMAT parameter:
ALTER SESSION SET NLS_DATE_FORMAT='YYYY/MM/DD HH:MI:SS';
Note that the previous statement only alters the default for the session in which it is executed. We use a custom format in our Oracle systems and to ensure that we get it on all sessions we use an after logon trigger:
create or replace TRIGGER NLS_Parameters_OnLogon AFTER LOGON ON SCHEMA BEGIN
-- This makes the database case insensitive for sorting and searching and sets the default date format for TO_CHAR and TO_DATE
EXECUTE IMMEDIATE 'ALTER SESSION SET NLS_COMP=LINGUISTIC';
EXECUTE IMMEDIATE 'ALTER SESSION SET NLS_SORT=BINARY_CI';
EXECUTE IMMEDIATE 'ALTER SESSION SET NLS_DATE_FORMAT=''YYYY/MM/DD HH:MI:SS''';
End;
It is possible to change the default date format for the whole Oracle server by editing some of the Oracle config files but since we have to deploy to client servers over which we have no control we use this method instead.
This article covers the same sort of ground I just have with a little more in the way of examples.
I'm using an Oracle DB and I'm trying to fetch data from its tables using PHP. One of the tables contains a date column which behaves strange to me.
When I open the table in my DB client (I'm using Navicat Lite) I see dates like "2007-11-29 10:15:42" but when I retrieve them with PHP and display the date it says "29-NOV-07". I use a simple SQL query and standard PHP functions (oci_parse, oci_execute, oci_fetch_array).
Why is the value from the DB converted to this (useless) format? How can I get the date just like it is stored in the DB? Thanks for your tips!
Oracle DATE datatype is a point in time, it has no format attached. When you transform a date to a string (to display if for example), the format applied to the date will be dependent upon your session parameters (implicit conversion). From what I remember of PHP, the retrieval functions will convert the date to a string automatically, using the NLS_DATE_FORMAT session parameter.
Either:
change the NLS_DATE_FORMAT beforehand with:
ALTER SESSION SET NLS_DATE_FORMAT='yyyy-mm-dd hh24:mi:ss'
or, if you want to specify another format in your query, you should explicitely ask for it:
SELECT to_char(my_date, 'yyyy-mm-dd hh24:mi:ss') ...
Update
Thanks to ThinkJet for the link to the PHP documentation:
DATE columns are returned as strings formatted to the current date format. The default format can be changed with Oracle environment variables such as NLS_LANG or by a previously executed ALTER SESSION SET NLS_DATE_FORMAT command.
i need to check for a specific DateTime value in my table from my code (VB.NET) and i don't know how to format the DateTime as a string. i've read that SQL Server will recognize my string if it's in either date, time, or date and time format. i mean:
'May 15, 2004'
'5/15/2004'
'20040515'
'2004 4 am'
will SQL Server recognize these strings as valid DateTime values? i'm curious because if i check the actual DateTime values in the table they are in this format:
2/2/2006 3:49:33 PM
Don't put the date/time value in the SQL query in the first place - use a parameterized query and then you don't need to know or care what format SQL Server would parse literals as. You put the placeholder in the SQL, and specify the value as a DateTime in the parameter collection.
You should be using parameterized SQL as a matter of course, in fact - not only does it get rid of formatting and parsing problems like this, but possibly more importantly it's the single most effective weapon against SQL injection attacks.
If not using a parameterized query, use CAST/CONVERT to explicitly change a string to a DATETIME:
SELECT CAST('2/2/2006 3:49:33 PM' AS DATETIME)
On my SQL Server 2005, that returns to me:
2006-02-02 15:49:33.000
Mind that the default date format in SQL Server can be different than what you provide.
This has always been safe that I have found:
YYYY-MM-DD HH:MI:SS
If you're comparing DateTime to DateTime, you don't have to worry about conversion, necessarilly, but yes, Sql Server (at least as of 2k8, and I believe 2k5 as well) will automatically parse a DateTime from a string. That is, if you pass '5/15/2004' it will see 5/15/2004 12:00:00 AM or something similar.
a better way, though, is to use SqlParameters in your SqlCommand from Code.