From what I have seen so far, when inserting into a table that has date value such as "27-10-2004", the following format DD-MON-YYYY is used
insert into tableName values('27-Oct-2004')
Is it possible to insert the date in its original format '27-10-2004' into the table? In general how many variations of this date may be considered correct for inserting into tables (this is without using any built-in functions, just SQL)?
Use a date literal in Oracle:
insert into tableName
values (DATE '2004-10-27');
This defines a date constant using the ISO standard format YYYY-MM-DD.
If you wanted to use a specific format -- which I wouldn't recommend -- then you can convert to a date using to_date():
insert into tableName
values (to_date('27-10-2004', 'DD-MM-YYYY'));
Any particular string that you use is interpreted based on system settings, so it can vary by language and geography.
Note: When inserting a value, you should include the column names. I assume that your code is just for illustrative purposes.
Related
I'm working on a table with a column, 'Expiry Date', as a varchar with all data formatted as DD/MM/YYYY.
The creator of the table has used the wrong type for this expiry date column and now the client needs to filter and show all records before and after the current date as the time. This means the type needs to be changed to date or datetime type to be able to use the CURDATE() function.
However, the current format of the values does not satisfy and wont allow the type to change unless the format is changed to YYYY-MM-DD (or similar).
Is there any way to mass format the values in this column and this column alone as there are thousands of entries and formatting one by one would be extremely time consuming.
Let me assume that you are using MySQL.
Perhaps the simplest method is to add a generated column that is a date:
alter table t add column expiry_date_date as
(str_to_date(expiry_date, '%d/%m/%Y'));
You can also fix the data:
update t
set expiry_date = str_to_date(expiry_date, '%d/%m/%Y');
This will implicitly convert the result of str_to_date() to a date, which will be in the YYYY-MM-DD format.
More importantly, you can then do:
alter table t modify column expiry_date date;
Here is a db<>fiddle.
You can do similar operations in other databases, but the exact code is a bit different.
What you need is an update on that column, but before doing it I suggest you to check if the result is what you want.
select replace(expiry_date, '/', '-') new_expiry_date
from table_name
If this returns the results you want you can run the following update:
update table_name
set expiry_date = replace(expiry_date, '/', '-')
Of course you will need to replace expiry_date and table_name with the names of your column and table.
I have a table with the following format:
CREATE TABLE perflog(
REQ_TIME TIMESTAMP,
RESP_TIME TIMESTAMP,
OPERATION VARCHAR2(50),
STATUS_CODE VARCHAR2(10),
STATUS_BODY VARCHAR2(30)
);
-I want to insert a timestamp in the following format: e.g. 2020-07-27T23:33:41.427330
-I'm getting the following error:
SQL> insert into perflog(REQ_TIME) VALUES(2020-07-27T23:33:41.427330);
SP2-0552: Bind variable "33" not declared.
I don't get how to declare the timestamp in order to insert dates like the above. Sorry if it is a noob question but I'm a begginer.
Simply wrapping your value in single quotes isn't enough:
insert into perflog(REQ_TIME) VALUES('2020-07-27T23:33:41.427330');
ORA-01843: not a valid month
The actual error you get will depend on your session's NLS settings (and it's possible it would work - for you, if you set your session up in a certain way - but then not necessarily for anyone else.)
Oracle has timestamp literals which you can use instead of to_timestamp(), but unfortunately they don't allow the "T":
insert into perflog(REQ_TIME) VALUES(TIMESTAMP '2020-07-27T23:33:41.427330');
ORA-01861: literal does not match format string
and you can't remove it within the call (e.g. with replace) as that then isn't a literal; so you would have to change the "T" to a space externally:
insert into perflog(REQ_TIME) VALUES(TIMESTAMP '2020-07-27 23:33:41.427330');
If you're stuck with a string with that format then use an explicitly to_timestamp() call to convert your string to the data type you want, supplying the matching format mask, including a character-literal `"T"':
insert into perflog(REQ_TIME)
VALUES(TO_TIMESTAMP('2020-07-27T23:33:41.427330', 'YYYY-MM-DD"T"HH24:MI:SS.FF6'));
db<>fiddle
It's worth noting that timestamps (and dates) do not have a specific human-readable format when stored in the database. Oracle uses one of several internal representations, depending on the flavour of datetime you're using. Your client, IDE or application will format that as a readable string when you query the data, usually using your session NLS settings again. To get the data back as a string in a specific format you should use to_char() with the appropriate format supplied.
db<>fiddle with some examples.
Use a timestamp literal using a space character instead of a T:
insert into perflog(REQ_TIME) VALUES( TIMESTAMP '2020-07-27 23:33:41.427330');
db<>fiddle
can we insert date into varchar2 in oracle without converting by to_char?
Oracle will convert the date into a string using what localization settings are in place during the insert. This is true not only of Oracle but of any database. For a date, that might commonly be in the format "DD-MON-YY".
Here is an example of inserting a date into a varchar2 column.
That said, you should not do this. You should be storing date/time values in the database using the correct data type -- and that would be either date or timestamp. If you want to insert a constant, then use the date or timestamp qualifier with the appropriate value following it.
This has been asked many times before and I tried quite a bit before posting this question. I have 2 columns on my SQL Server table where the dates are stored as CHAR(8) yyyymmdd format. When I try to insert this to another table with date column, I get:
Conversion failed when converting date and/or time from character string.
The typecasting that I used is:
,CAST(convert(char(10),qrda.BillFromDate,120) AS DATE) AS [BillStartDate]
,CAST(convert(char(10),qrda.BillToDate,120) AS DATE) AS [BillEndDate]
With the above code, I am trying to make it SQL Server readable date format and then typecasting it to DATE so that I can insert it to the destination table without any other transformations. Not sure where I am going wrong with this.
Since date are stored in the following format yyyyMMdd you can insert these values without any need to use CONVERT or CAST functions, since this format can be implicitly converted to DATE.
If the data contains invalid values such as 00000000, you can use TRY_CONVERT or TRY_PARSE function to convert these values to NULL
Example:
CREATE TABLE #TBLTEMP(datecolumn DATETIME)
INSERT INTO #TBLTEMP(datecolumn)
VALUES ('20180101')
INSERT INTO #TBLTEMP(datecolumn)
VALUES (TRY_PARSE('00000000' as DATETIME))
SELECT * FROM #TBLTEMP
Result:
From the example above, you can see that 20180101 was inserted succesfly without any casting, while TRY_PARSE function converted the invalid value 00000000 to NULL.
You can use the following syntax:
INSERT INTO TargetTable(DateColumn)
SELECT TRY_PARSE([CharColumn] as DATETIME
FROM SourceTable
References
Understanding SQL Server’s TRY_PARSE and TRY_CONVERT functions
TRY_PARSE (Transact-SQL)
Sorry for the trouble folks, but looks like this is bad production data where some values are literally '00000000'. I dont know how this flows into our system, but since the source table columns are CHAR(8), this is a valid value. Not so much for me.
Question1:
Do i have to use to_date while inserting date?
INSERT INTO some_table (date1, date2)
VALUES (to_date('2012-10-24','YYYY-MM-DD'), to_date('2012-10-24','YYYY-MM-DD'));
Or can just insert as string? Will everything be OK this way too? I've tried and it worked.
INSERT INTO some_table (date1, date2)
VALUES ('2012-10-24',2012-10-24');
Question2:
What happens if i won't name columns that i'm inserting into? It works, but my question is if it inserts randomly now or it takes order of columns during creation of table?
INSERT INTO some_table
VALUES ('2012-10-24',2012-10-24');
1 seems to only work with the 'YYYY-MM-DD' format:
http://docs.oracle.com/cd/B28359_01/server.111/b28286/sql_elements003.htm#SQLRF51049 says
You can specify a DATE value as a string literal ... to specify a DATE value as a literal, you must use the Gregorian calendar. You can specify an ANSI literal... The ANSI date literal contains no time portion, and must be specified in the format 'YYYY-MM-DD'.
However, it might work with time if you use the
Alternatively you can specify an Oracle date value... The default date format for an Oracle DATE value is specified by the initialization parameter NLS_DATE_FORMAT.
For question 2, it uses the order at definition of the table. However you have to give values for all columns in that case.
Oracle supports Standard SQL date literals (since 9i).
It's DATE followed by a string with 'yyyy-mm-dd' format
DATE '2014-05-10'
It's much shorter than TO_DATE and it's independent of any NLS settings.
Similar for timestamps:
TIMESTAMP '2014-05-10 09:52:35'
Regarding your 2nd question: It's the order of columns as defined within the CREATE TABLE.
You could even do it like this one:
ALTER SESSION SET NLS_DATE_FORMAT = 'MM:YYYY:DD';
INSERT INTO some_table (date1) VALUES ('05:2014:10');
...but doing it like this is not recommended. Use TO_DATE or DATE Literal, e.g. DATE '2014-05-10' instead. It makes your life easier.