I could fix this issue by declaring the variable as DATE and not as VARCHAR.
I have a pre-configured constant varchar2 value in a table.
I have declared lv_constants_config as VARCHAR2 and not as DATE.
I think that is the reason why I am facing problem.
SELECT * FROM constants_config
------------------------------
constant1
---------
01/01/3000
In my PL/SQL code I am retrieving this value as,
SELECT TO_DATE(constant1,'MM/DD/YYYY') --I also tried with RRRR instead of YYYY.
INTO lv_constants_config
FROM constants_config;
I am comparing this value with the value input by the User (from UI).
IF iv_input_date > lv_constants_config
THEN
--do this
ELSE
--do that
END IF;
My problem is 3000 is getting wrongly interpreted as 00.
Eg., 01/01/3000 is getting interpreted as 1st Jan, 2000
01/01/3049 is getting interpreted as 1st Jan, 2049
01/01/3050 is getting interpreted as 1st Jan, 2050
How can I compare dates with century value as it is?
Related
I am trying to calculate the difference between dates. I only need the decimal of a day so date - date is all I need.
The issue I have is, this works for some records but not others, with no real pattern. Using the below:
select (case when c.call_answered_date is null then c.call_ended_date - c.call_entered_queue_date else 0 end),
C.CALL_ENTERED_SYSTEM_DATE, C.CALL_ENTERED_QUEUE_DATE, C.CALL_ENDED_DATE
I get
abd_wait call_entered_system_date call_entered_queue_date call_ended_date
-------- ------------------------ ----------------------- ---------------
5.78703703703704E-5 06/01/2020 12:30:00 06/01/2020 12:30:11 06/01/2020 12:30:16
0.000844907407407407 06/01/2020 12:35:38 06/01/2020 12:35:49 06/01/2020 12:37:02
So the second line works as expected, the first does not. But I do not know why.
I need them to all be a decimal of a day like the second line.
Please help.
The first line has the correct value and is just in scientific notation: 5.78703703703704E-5
is the same as: 0.0000578703703703704 which is 5 seconds expressed as a fraction of a day: (16-11)/24/60/60. The value is still a (decimal) number it is just displayed in a slightly different format.
If you want it as a fixed formatted decimal string then use TO_CHAR to give the number an explicit format:
select case
when c.call_answered_date is null
then TO_CHAR(
c.call_ended_date - c.call_entered_queue_date,
'0.000000000000000000'
)
else '0'
end,
C.CALL_ENTERED_SYSTEM_DATE,
C.CALL_ENTERED_QUEUE_DATE,
C.CALL_ENDED_DATE
FROM your_table c
I need to calculate age for the people and their birthdates are saved in varchar2 like 19900130, and some people don't have their birthdates recorded and default value is 00000000.
Here is my code:
SELECT
e.id_number,
e.birth_dt,
(CASE WHEN SUBSTR(e.birth_dt, 1, 4) = '0000' THEN 0
WHEN SUBSTR(e.birth_dt, 1, 4) <> '0000' THEN
ROUND(MONTHS_BETWEEN(SYSDATE, TO_DATE(e.birth_dt, 'YYYYMMDD')) / 12)
ELSE -1
END) age
FROM employee e
The error is:
ORA-01843: Not a valid month
Is anything wrong? I couldn't figure out.
Is anything wrong? Yes, your case is not covering the possibility that some strings have something other than 01, 02, ..., 12 in character positions 5 and 6. Likewise, your case is not covering the possibility that the day of the month character positions are something other than 01, 02, ... 31 (and the covering of the possibility that a day of the month is not valid for a particular month).
If I were you, I'd add a proper date column, modify the app to populate both columns, fix the app so that it stops putting bad data into the table, decide what to do with the bad data, modify the app to stop populating the varchar2 column, and then drop the varchar2 column.
I'm trying to figure out how to compare the result of a date substraction in a where clause.
Clients subscribed to a service and therefore are linked to a subscription that has an end date. I want to display the list of subscriptions that will come to an end within the next 2 weeks.
I did not designed the databse but noticed that the End_Date column type is a varchar and not a date.. I can't change that.
My problem is the following:
If I try to select the result of the substraction for example with this request:
SELECT(TO_DATE(s.end_date,'YYYY-MM-DD') - TRUNC(SYSDATE)) , s.name
from SUBSCRIPTION s WHERE s.id_acces = 15
This will work and give me the number of days between the end of the subscription and the current date.
BUT now, if I try to include the exact same request in a clause where for comparison:
SELECT s.name
from SUBSCRIPTION S
WHERE (TO_DATE(s.end_date,'YYYY-MM-DD') - TRUNC(SYSDATE)) between 0 and 16
I will get an error: "ORA-01839 : date not valid for month specified".
Any help would be appreciated..
Somewhere in the table you have your date formatted in a different way from YYYY-MM-DD. In your first query you check a certain row (or a set of rows, s.id_acces = 15), which is probably ok, but in the second you scan through all the table.
Try finding these rows with something like,
select end_date from subscription
where not regexp_like(end_date, '[0-9]{4}-[0-9]{2}-[0-9]{2}')
Check your DD value (ie: day of the month). This value must be between 1 and the number of days in the month.
January - 1 to 31
February - 1 to 28 (1 to 29, if a leap year)
March - 1 to 31
April - 1 to 30
May - 1 to 31
June - 1 to 30
July - 1 to 31
August - 1 to 31
September - 1 to 30
October - 1 to 31
November - 1 to 30
December - 1 to 31
" the End_Date column type is a varchar and not a date.. I can't
change that."
If you can't change the date you'll have to chang3 the data. You can identify the rogue values with this function:
create or replace check_date_format (p_str in varchar2) return varchar2
is
d date;
begin
d := to_date(p_str,'YYYY-MM-DD');
return 'VALID';
exception
when others then
return 'INVALID';
end;
You can use this function in a query:
select sid, end_date
from SUBSCRIPTION
where check_date_format(end_date) != 'VALID';
Your choices are:
fix the data so all the dates are in the same format
fix the data and apply a check constraint to enforce future validity
write a bespoke MY_TO_DATE() function which takes a string and applies lots of different date format masks to it in the hope of getting a successful conversion.
I have the following query that I am attempting to use as a COMMAND in a crystal report that I am working on.
SELECT * FROM myTable
WHERE to_date(myTable.sdate, 'MM/dd/yyyy') <= {?EndDate}
This works fine, however my only concern is that the date may not always be in the correct format (due to user error). I know that when the to_date function fails it throws an exception.. is it possible to handle this exception in such a way that it ignores the corresponding row in my SELECT statement? Because otherwise my report would break if only one date in the entire database is incorrectly formatted.
I looked to see if Oracle offers an isDate function, but it seems like you are supposed to just handle the exception. Any help would be greatly appreciated. Thanks!!
Echoing Tony's comment, you'd be far better off storing dates in DATE columns rather than forcing a front-end query tool to find and handle these exceptions.
If you're stuck with an incorrect data model, however, the simplest option in earlier versions is to create a function that does the conversion and handles the error,
CREATE OR REPLACE FUNCTION my_to_date( p_date_str IN VARCHAR2,
p_format_mask IN VARCHAR2 )
RETURN DATE
IS
l_date DATE;
BEGIN
l_date := to_date( p_date_str, p_format_mask );
RETURN l_date;
EXCEPTION
WHEN others THEN
RETURN null;
END my_to_date;
Your query would then become
SELECT *
FROM myTable
WHERE my_to_date(myTable.sdate, 'MM/dd/yyyy') <= {?EndDate}
Of course, you'd most likely want a function-based index on the MY_TO_DATE call in order to make this query reasonably efficient.
In 12.2, Oracle has added extensions to the to_date and cast functions to handle conversions that error
SELECT *
FROM myTable
WHERE to_date(myTable.sdate default null on conversion error, 'MM/dd/yyyy') <= {?EndDate}
You could also use the validate_conversion function if you're looking for all the rows that are (or are not) valid dates.
SELECT *
FROM myTable
WHERE validate_conversion( myTable.sdate as date, 'MM/DD/YYYY' ) = 1
If your data is not consistent and dates stored as strings may not be valid then you have 3 options.
Refactor your DB to make sure that the column stores a date datatype
Handle the exception of string to date in a stored procedure
Handle the exception of string to date in a (complex) record selection formula
I would suggest using the first option as your data should be consistent.
The second option will provide some flexibility and speed as the report will only fetch the rows that are needed.
The third option will force the report to fetch every record in the table and then have the report filter down the records.
I have the same problem... an old legacy database with varchar fields for dates and decades of bad data in the field. As much as I'd like to, I can't change the datatypes either. But I came up with this solution to find if a date is current, which seems to be what you're doing as well:
select * from MyTable
where regexp_like(sdate, '[0-1][0-9].[0-3][0-9].[0-9][0-9][0-9][0-9]')
-- make sure it's in the right format and ignore rows that are not
and substr(sdate,7,10) || substr(sdate,1,2) || substr(sdate,4,5) >= to_char({?EndDate}, 'YYYYMMDD')
-- put the date in ISO format and do a string compare
The benefit of this approach is it doesn't choke on dates like "February 30".
Starting from Oracle 12c there is no need to define a function to catch the conversion exception.
Oracle introduced an ON CONVERSION ERROR clause in the TO_DATE function.
Basically the clause suppress the error in converting of an invalid date string (typical errors are ORA-01843, ORA-01841, ORA-011861, ORA-01840) and returns a specified default value or null.
Example of usage
select to_date('2020-99-01','yyyy-mm-dd') from dual;
-- ORA-01843: not a valid month
select to_date('2020-99-01' default null on conversion error,'yyyy-mm-dd') from dual;
-- returns NULL
select to_date('2020-99-01' default '2020-01-01' on conversion error,'yyyy-mm-dd') from dual;
-- 01.01.2020 00:00:00
Solution for the Legacy Application
Let's assume there is a table with a date column stored as VARCHAR2(10)
select * from tab;
DATE_CHAR
----------
2021-01-01
2021-99-01
Using the above feature a VIRTUAL DATE column is defined, that either shows the DATE or NULL in case of the conversion error
alter table tab add (
date_d DATE as (to_date(date_char default null on conversion error,'yyyy-mm-dd')) VIRTUAL
);
select * from tab;
DATE_CHAR DATE_D
---------- -------------------
2021-01-01 01.01.2021 00:00:00
2021-99-01
The VIRTUAL column can be safely used because its format is DATE and if required an INDEX can be set up on it.
select * from tab where date_d = date'2021-01-01';
Since you say that you have "no access" to the database, I am assuming that you can not create any functions to help you with this and that you can only run queries?
If that is the case, then the following code should get you most of what you need with the following caveats:
1) The stored date format that you want to evaluate is 'mm/dd/yyyy'. If this is not the case, then you can alter the code to fit your format.
2) The database does not contain invalid dates such as Feb 30th.
First, I created my test table and test data:
create table test ( x number, sdate varchar2(20));
insert into test values (1, null);
insert into test values (2, '01/01/1999');
insert into test values (3, '1999/01/01');
insert into test values (4, '01-01-1999');
insert into test values (5, '01/01-1999');
insert into test values (6, '01-01/1999');
insert into test values (7, '12/31/1999');
insert into test values (8, '31/12/1999');
commit;
Now, the query:
WITH dates AS (
SELECT x
, sdate
, substr(sdate,1,2) as mm
, substr(sdate,4,2) as dd
, substr(sdate,7,4) as yyyy
FROM test
WHERE ( substr(sdate,1,2) IS NOT NAN -- make sure the first 2 characters are digits
AND to_number(substr(sdate,1,2)) between 1 and 12 -- and are between 0 and 12
AND substr(sdate,3,1) = '/' -- make sure the next character is a '/'
AND substr(sdate,4,2) IS NOT NAN -- make sure the next 2 are digits
AND to_number(substr(sdate,4,2)) between 1 and 31 -- and are between 0 and 31
AND substr(sdate,6,1) = '/' -- make sure the next character is a '/'
AND substr(sdate,7,4) IS NOT NAN -- make sure the next 4 are digits
AND to_number(substr(sdate,7,4)) between 1 and 9999 -- and are between 1 and 9999
)
)
SELECT x, sdate
FROM dates
WHERE to_date(mm||'/'||dd||'/'||yyyy,'mm/dd/yyyy') <= to_date('08/01/1999','mm/dd/yyyy');
And my results:
X SDATE
- ----------
2 01/01/1999
The WITH statement will do most of the validating to make sure that the sdate values are at least in the proper format. I had to break out each time unit month / day / year to do the to_date evaluation because I was still getting an invalid month error when I did a to_date on sdate.
I hope this helps.
Trust this reply clarifies...
there is no direct EXCEPTION HANDLER for invalid date.
One easy way is given below once you know the format like DD/MM/YYYY then below given REGEXP_LIKE function will work like a charm.
to_date() also will work, when invalid_date is found then cursor will goto OTHERS EXCEPTION. given below.
DECLARE
tmpnum NUMBER; -- (1=true; 0 = false)
ov_errmsg LONG;
tmpdate DATE;
lv_date VARCHAR2 (15);
BEGIN
lv_date := '6/2/2018'; -- this will fail in *regexp_like* itself
lv_date := '06/22/2018'; -- this will fail in *to_date* and will be caught in *exception WHEN OTHERS* block
lv_date := '07/03/2018'; -- this will succeed
BEGIN
tmpnum := REGEXP_LIKE (lv_date, '[0-9]{2}/[0-9]{2}/[0-9]{4}');
IF tmpnum = 0
THEN -- (1=true; 0 = false)
ov_errmsg := '1. INVALID DATE FORMAT ';
DBMS_OUTPUT.PUT_LINE (ov_errmsg);
RETURN;
END IF;
tmpdate := TO_DATE (lv_date, 'DD/MM/RRRR');
--tmpdate := TRUNC (NVL (to_date(lv_date,'DD/MM/RRRR'), SYSDATE));
tmpnum := 1;
EXCEPTION
WHEN OTHERS
THEN
BEGIN
tmpnum := 0;
ov_errmsg := '2. INVALID DATE FORMAT ';
DBMS_OUTPUT.PUT_LINE (ov_errmsg || SQLERRM);
RETURN;
END;
-- continue with your other query blocks
END;
-- continue with your other query blocks
DBMS_OUTPUT.PUT_LINE (tmpnum);
END;
Question:
Is it possible to have a column name in a select statement changed based on a value in it's result set?
For example, if a year value in a result set is less than 1950, name the column OldYear, otherwise name the column NewYear. The year value in the result set is guaranteed to be the same for all records.
I'm thinking this is impossible, but here was my failed attempt to test the idea:
select 1 as
(case
when 2 = 1 then "name1";
when 1 = 1 then "name2")
from dual;
You can't vary a column name per row of a result set. This is basic to relational databases. The names of columns are part of the table "header" and a name applies to the column under it for all rows.
Re comment: OK, maybe the OP Americus means that the result is known to be exactly one row. But regardless, SQL has no syntax to support a dynamic column alias. Column aliases must be constant in a query.
Even dynamic SQL doesn't help, because you'd have to run the query twice. Once to get the value, and a second time to re-run the query with a different column alias.
The "correct" way to do this in SQL is to have both columns, and have the column that is inappropriate be NULL, such as:
SELECT
CASE WHEN year < 1950 THEN year ELSE NULL END AS OldYear,
CASE WHEN year >= 1950 THEN year ELSE NULL END AS NewYear
FROM some_table_with_years;
There is no good reason to change the column name dynamically - it's analogous to the name of a variable in procedural code - it's just a label that you might refer to later in your code, so you don't want it to change at runtime.
I'm guessing what you're really after is a way to format the output (e.g. for printing in a report) differently depending on the data. In that case I would generate the heading text as a separate column in the query, e.g.:
SELECT 1 AS mydata
,case
when 2 = 1 then 'name1'
when 1 = 1 then 'name2'
end AS myheader
FROM dual;
Then the calling procedure would take the values returned for mydata and myheader and format them for output as required.
You will need something similar to this:
select 'select ' || CASE WHEN YEAR<1950 THEN 'OLDYEAR' ELSE 'NEWYEAR' END || ' FROM TABLE 1' from TABLE_WITH_DATA
This solution requires that you launch SQLPLUS and a .sql file from a .bat file or using some other method with the appropriate Oracle credentials. The .bat file can be kicked off manually, from a server scheduled task, Control-M job, etc...
Output is a .csv file. This also requires that you replace all commas in the output with some other character or risk column/data mismatch in the output.
The trick is that your column headers and data are selected in two different SELECT statements.
It isn't perfect, but it does work, and it's the closest to standard Oracle SQL that I've found for a dynamic column header outside of a development environment. We use this extensively to generate recurring daily/weekly/monthly reports to users without resorting to a GUI. Output is saved to a shared network drive directory/Sharepoint.
REM BEGIN runExtract1.bat file -----------------------------------------
sqlplus username/password#database #C:\DailyExtracts\Extract1.sql > C:\DailyExtracts\Extract1.log
exit
REM END runExtract1.bat file -------------------------------------------
REM BEGIN Extract1.sql file --------------------------------------------
set colsep ,
set pagesize 0
set trimspool on
set linesize 4000
column dt new_val X
select to_char(sysdate,'MON-YYYY') dt from dual;
spool c:\DailyExtracts\&X._Extract1.csv
select '&X-Project_id', 'datacolumn2-Project_Name', 'datacolumn3-Plant_id' from dual;
select
PROJ_ID
||','||
replace(PROJ_NAME,',',';')-- "Project Name"
||','||
PLANT_ID-- "Plant ID"
from PROJECTS
where ADDED_DATE >= TO_DATE('01-'||(select to_char(sysdate,'MON-YYYY') from dual));
spool off
exit
/
REM ------------------------------------------------------------------
CSV OUTPUT (opened in Excel and copy/pasted):
old 1: select '&X-Project_id' 'datacolumn2-Project_Name' 'datacolumn3-Plant_id' from dual
new 1: select 'MAR-2018-Project_id' 'datacolumn2-Project_Name' 'datacolumn3-Plant_id' from dual
MAR-2018-Project_id datacolumn2-Project_Name datacolumn3-Plant_id
31415 name1 1007
31415 name1 2032
32123 name2 3302
32123 name2 3384
32963 name3 2530
33629 name4 1161
34180 name5 1173
34180 name5 1205
...
...
etc...
135 rows selected.