I'm trying to add a column named order to my table. I realize that order is a reserved word in SQL. So, how do I do it?
My command:
alter table mytable add column order integer;
I've also tried:
alter table mytable add column 'order' integer;
PostgreSQL 9.1.
Use this:
alter table mytable add column "order" integer;
But, you might want to consider using a non-reserved name instead, like sort_order or something similar that reflects what the column is used for (and isn't a reserved word).
I think you don't need "column". Plus "order" is a keyword in SQL, so you should use a different name for your column. Follow this syntax:
ALTER TABLE table_name ADD column_name datatype
Source: W3Schools
ALTER TABLE table_name
ADD COLUMN "order" integer
You are using order which is a reserved keyword you should consider renaming that to something like orders. And the problem should go away.
Related
I have a PostgreSQL (9.0) database with a column card_id which is currently of type integer
I need to change this to type text
What is the most best way to achieve this?
The only solution I can find involves creating a temporary column, dropping the original then renaming, I thought they might be a better method??
Have you tried what the fine manual suggests:
ALTER TABLE table ALTER COLUMN anycol TYPE anytype;
Depending on the current and the new type you may need to add USING ... to this statement.
But in your specific case that should not be necessary I believe.
ALTER TABLE table ALTER COLUMN card_id SET DATA TYPE text;
How to do something like this...
alter table customer_schedule add (week_number as (TO_CHAR((SCHEDULE_DATE),'iw'))
Wherein SCHEDULE_DATE is one of the existing columns in table
This is where you need VIRTUAL COLUMN. If you are on 11g and up, you could certainly do -
alter table table_name
add (column_name [data_type] [generated always] as (column_expression) [virtual]);
In your case, it will be something like -
alter table customer_schedule add (week_number data_type generated always as (TO_CHAR((SCHEDULE_DATE),'iw') VIRTUAL)
On 9i, you cannot use virtual columns, so I'd probably go with a view:
create view customer_schedule_view as
select
c.*,
to_char(c.schedule_date, 'iw')) week_number
from
customer_schedule c;
Of course, in your forms you need then to select from the view rather from the table.
The default keyword is supposed to let you store values when there is some value missing, but due to restrictions, you cannot use a column name
A DEFAULT expression cannot contain references to PL/SQL functions or to other columns, the pseudocolumns LEVEL, PRIOR, and ROWNUM, or date constants that are not fully specified.
I think a row-level BEFORE INSERT/UPDATE trigger should do want you want to do.
I have a table in a database created in oracle 10G. It contains a column of type 'VARCHAR' and stores date as string in this format-> 'dd-mon-yyyy' eg: '12-aug-2008'. Now I want to change the datatype of this column from VARCHAR to DATE. but when i perfrom this query->
ALTER TABLE sales_order
MODIFY COLUMN delivery_date DATE;
I get following error
ORA-00905: missing keyword
I have also tried :
ALTER TABLE sales_order
ALTER COLUMN delivery_date DATE;
I got the error :
ORA-01735: invalid ALTER TABLE option
However when i try to add a fresh column with DATE datatype it works fine.
example :
ALTER TABLE sales_order
ADD delivery DATE;
So, can anybody suggest me a way to change the datatype without deleting the column and its data.
It's the first one, with a slight modification:
ALTER TABLE sales_order MODIFY (delivery_date DATE);
But I'm not sure that will work for those particular datatypes and it also may not work depending on the current data.
You may find it necessary in that case to:
create a new column X of date type.
populate X based on the old column (may need several passes of data fix-ups to work).
delete old column.
rename X to old column name.
Although its a pretty old question, I'll put my solution here for people seeking for a solution:
Here's my solution and it works perfectly.
ALTER TABLE `sales_order` CHANGE `delivery_date` `delivery_date` DATE;
Thank you
modify a column then syntax is:-
alter table table_name modify column_name datatype;
but when you modify the column datatype column must be empty
Thanks for the hints! This got it for me.
alter table Table_Name
Alter column Column_Name datatype
GO
I too was needing to change from a VARCHAR to a date. I am working in SQL 2008 R2. I have found that if I bring in dates as a char or varchar and then change the type to date or datetime, I can catch time/date problems more easily.
THIS STATEMENT WILL FAIL IF YOUR DATA HAS ANY BAD DATES. (I break the date down into sections to find the bad date so I can correct and then I can alter the column type.)
Alternatively, you could create a new column, in which the data type is DATE. then pass the data in your varchar as a date .then drop your initial column and finally rename your new column to what it was initially...code below.
ALTER TABLE my_table ADD (new_col DATE);
UPDATE my_table SET new_col=TO_DATE(old_col,'MM/DD/YYYY');
ALTER TABLE my_table DROP (old_col);
ALTER TABLE my_table RENAME COLUMN new_col TO old_col;
alter table employee add (DOB varchar(10));
if you add a column with datatype varchar and if you want to modify the datatype of DOB then you can use this command ->
alter table employee modify(DOB date);
Now the table is modified.
Before posting this question, I have tried so many things but that was not helpful for me.
I want to rename the column of table at sql server 2005, following query I have run at sql server2005:
1) ALTER TABLE Details RENAME COLUMN
AccountID TO UID; but it gives me the
error: Incorrect syntax near the
keyword 'COLUMN'.
2)I have added one new column in the
table by query: ALTER TABLE Details
ADD BID uniqueidentifier; and then I
want to set the coulmn property to not
null .
How can i do that?
Thanks in advance
AS
Use sp_Rename 'TableName.Column', 'NewColumnName', 'COLUMN'.
In order to do your second part of the question, you'll need to do:
ALTER TABLE myTable
ADD myColumn UNIQUEIDENTIFIER NOT NULL DEFAULT 'some default value'
If you don't want to specify a default value, you'll have to first create the column with NULL. Once the column is created, you can then populate with your desired values and then re-alter the column to NOT NULL.
1) Instead of using ALTER TABLE, why not use sp_rename? For example:
EXEC sp_rename 'Details.[AccountID]', 'title', 'UID'
2) You can use ALTER TABLE Details ALTER COLUMN BID NOT NULL, but you'll probably want to specify a default value for it also, if the table already has data in it.
How do I add a column after another column within MS SQL by using SQL query?
TempTable
ID int,
Type nvarchar(20),
Active bit
NewTable
ID int,
Type nvarchar(20),
Description text,
Active bit
That is what I want, how do I do that
Assuming MySQL (EDIT: posted before the SQL variant was supplied):
ALTER TABLE myTable ADD myNewColumn VARCHAR(255) AFTER myOtherColumn
The AFTER keyword tells MySQL where to place the new column. You can also use FIRST to flag the new column as the first column in the table.
It depends on what database you are using. In MySQL, you would use the "ALTER TABLE" syntax. I don't remember exactly how, but it would go something like this if you wanted to add a column called 'newcol' that was a 200 character varchar:
ALTER TABLE example ADD newCol VARCHAR(200) AFTER otherCol;
In a Firebird database the AFTER myOtherColumn does not work but you can try re-positioning the column using:
ALTER TABLE name ALTER column POSITION new_position
I guess it may work in other cases as well.