How to Create a ORACLE Table to store Appointment Time - sql

I am trying to add to my current appointment table on ORACLE to store time of the appointment
ALTER TABLE APPOINTMENT
add (Timeofappointment to_date NOT NULL)
Here the code seems to be fine but the function to_date, or the way I am writing it don't seem to be working.
Any suggestion as I have not found one to be able to work online.
I want it to store time like this: 13:00

You'll have to use the DATE datatype to store the appointment time. Here's a quick sample to get you started.
create table mydate(i NUMBER, d date)
insert into mydate values(1, TO_DATE('2014-03-14 16:24','YYYY-MM-DD HH24:MI'));
SELECT * FROM mydate
You'll need to add the column to your table and use similar format. When you make appointments you definitely need to consider the date as well as time. Just time by itself will have little value.

Related

Display Now date and Time in SQl table column

I want to be able to have todays date and time now in a table column
If my table is say Table1, basically it should display the time and date when
SELECT * FROM Table1 is run.
I've tried the following but they just show the time from the moment in time I assign the value to column
ALTER TABLE Table1
ADD TodaysDate DateTime NOT NULL DEFAULT GETDATE()
and
ALTER TABLE Table1
ADD TodaysDate DateTime
UPDATE Table1
SET TodaysDate = GETDATE()
Hope this is clear. any help is appreciated.
Thanks
In SQL Server you can use a computed column:
alter table table1 add TodaysDate as (cast(getdate() as date));
(use just getdate() for the date and time)
This adds a "virtual" column that gets calculated every time it is referenced. The use of such a thing is unclear. Well, I could imagine that if you are exporting the data to a file or another application, then it could have some use for this to be built-in.
I hope this clarifies your requirement.
The SQL Server columns with default values stores the values inside the table. When you select the values from table, the stored date time will be displayed.
There are 2 options I see without adding the column to the table itself.
You can use SELECT *, GETDATE() as TodaysDate FROM Table1
You can create a view on top of Table 1 with additional column like
CREATE VIEW vw_Table1
AS
SELECT *, GETDATE() as TodaysDate FROM dbo.Table1
then you can query the view like you mentioned (without column list)
SELECT * FROM vw_Table1
This will give you the date and time from the moment of the execution of the query.

Oracle 10 SQL - How to use a "00:00" time format in a constraint

Small entry level question with Oracle 10 SQL. I'm creating a table with a column with a "date" type which is supposed to hold values looking like this : "00:00". I have a constraint with checks the time to be between 00:00 and 23:00.
Now, what I can't quite grasp is how to approach the problem. I do feel like I'm missing something quite basic but I can't quite figure out what...
Do I :
1) Extract and check the date inside my constraint? If so, is there a way to do that? Can I insert data looking like this : TO_DATE('13-AUG-66 12:56','DD-MON-YY HH:MI'), and use some kind of "Extract" function inside my constraint?
2) The exercise in question does mention the date type for that particular column. By default, I assume that it doesn't hold hours and needs to be modified using alter_session?
A constraint only enforces a restriction. It cannot modify data. A BEFORE INSERT trigger can modify data but is generally less efficient than a constraint.
If you want to create a constraint that ensures that the time component is always midnight
CREATE TABLE table_name (
col DATE CHECK( col1 = TRUNC( col ))
);
If you want to create a trigger that modifies the data
CREATE OR REPLACE TRIGGER trg_trunc_dt
BEFORE INSERT ON table_name
FOR EACH ROW
BEGIN
:new.date_column := TRUNC( :new.date_column );
END;
A DATE always contains a day and a time component. Your client may or may not display either component. Many clients will use implicit data type conversion in which case the session's NLS_DATE_FORMAT controls how a DATE is converted to a VARCHAR2 and what elements are incorporated into the string.
A date type always has a date part and a time part. It is just a value and has thus no formatting. If you display a time as 22:50 or 10:50pm for example is up to you. You either rely on your settings with to_char(mydate) or specify a format to_char(mydate,'hh24:mi').
This said, you can simply use the time part of your column and ignore the date part. If you want to avoid confusion about different dates being stored, you can use a trigger setting the date part to 01.01.0001 for instance:
create or replace Trigger trg_datetable_datepart
before insert or update of mydate on datetable
for each row
begin
:new.mydate := to_date( '01.01.0001 ' || to_char(:new.mydate, 'hh24:mi') , 'dd.mm.yyyy hh24:mi' );
end;
To avoid inserts of times after 23h you would write a check constraint:
alter table datetable add constraint check_datetable_timepart check ( to_char(mydate, 'hh24:mi') <= '23:00' );

how to create automatic system date in sql without store whenever click the button

Hi I have one button named "Pay". User click so many times this button. Everytime it will create the current date in the column date in the table purchase.
How to do this in sql server 2008? Any hope?
To insert a record with corrent timestamp you can write a sql width CURRENT_TIMESTAMP as follows:
INSERT INTO Orders (date) VALUES(CURRENT_TIMESTAMP)
If you have other columns ont the Orders table, your SQL will go like as follows:
INSERT INTO Orders (date,....) VALUES(CURRENT_TIMESTAMP,.....)
This function CURRENT_TIMESTAMP is the ANSI SQL equivalent to GETDATE(), and you can also write this as fllows:
INSERT INTO Orders (date) VALUES(GETDATE())
The document is here.
http://msdn.microsoft.com/en-us/library/ms188751(v=sql.90).aspx
while inserting into table insert this value for the column where you want to save current date details DateTime.Now

using UPDATE, SELECTand INSERT INTO statements altogther in MS Access

I have an MS access project in which the tabel of transactions contains as many as 70 records per day. they are common in one parameter, the Date of today.
the normal way to start entering data is to go to teh table and copy records of yesterday then paste them as new records, then changing date from yesterday to today date.
What I need is to use SQL statements to achieve this. I can say that
step 1: use insert into to input the new records in the table.
Step 2: use update statement to change the date.
Step 3: use the select statement to select the records which will have the date to be changed.
How to combine the use of these statements altogther.
thanks
You need something on the lines of:
INSERT INTO Table (Field, Field, Field, ADate)
SELECT Field,Field,Field,Date() As ADate
FROM Table WHERE ADate = Date()-1
Or just change the default value of the date field in the table to Date(), or Now(), and only insert the other fields. Date will then be automatically filled in as today.

SQL - how to check table for new data?

I need to create a stored procedure that upon exceution checks if any new rows have been added to a table within the past 12 hours. If not, an warning email must be sent to a recipient.
I have the procedures for sending the email, but the problem is the query itself. I imagine I'd have to make an sql command that uses current date and compares that to the dates in the rows. But I'm a complete beginner in SQL so I can't even use the right words to find anything on google.
Short version:
Using MS SQL Server 2005, how can I check against the dates, then return a result based on whether new rows were created within the last 12 hours, and use that result to decide whether or not to send email?
Something like this should do what you wish.
Select ID
from TableName
where CreatedDate >= dateadd(hour,-12,getDate())
Hope this is clear but please feel free to pose further questions.
Cheers, John
Say your date field in the table is 'CreateDate' and it's of type DateTime.
Your time to compare with is: GETDATE()
(which returns date + time)
To get the datetime value of 12 hours before that, is done using DATEADD:
DATEADD(hour, -12, GETDATE())
so if we want the # of rows added in the last 12 hours, we'll do:
SELECT COUNT(*)
FROM Table
WHERE CreateDate >= DATEADD(hour, -12, GETDATE())
in your proc, you've to store the result of this query into a variable and check if it's > 0, so:
DECLARE #amount int
SELECT #amount=COUNT(*)
FROM Table
WHERE CreateDate >= DATEADD(hour, -12, GETDATE())
and then you'll check the #amount variable if it's > 0.
You could use a trigger, this link has several examples: http://msdn.microsoft.com/en-us/library/aa258254(SQL.80).aspx
USE pubs
IF EXISTS (SELECT name FROM sysobjects
WHERE name = 'reminder' AND type = 'TR')
DROP TRIGGER reminder
GO
CREATE TRIGGER reminder
ON titles
FOR INSERT, UPDATE, DELETE
AS
EXEC master..xp_sendmail 'MaryM',
'Don''t forget to print a report for the distributors.'
GO
If you do not want something for each insert/update, you could copy data to a another table then examine that table every 12 hours, report on the rows in it, then delete them...
assuming you have on this table :
- either a unique id autoincrementing
- either a created_timestamp field containing the timestamp of creation of the row
-> have a new table
reported_rows
- report_timestamp
- last_id_seen
(OR)
- last_timestamp_seen
fill the reported row each time you send your email with the actual value
and before sending the email, check with the previous values, so you know what rows have been added
If the table has an identity field, you could also save the max value (as a bookmark) and next time check if there are any rows with an ID greater than your saved bookmark. May be faster if the key is the clustered key.