I tried to insert some rows into SQL server database and throws an error:
Conversion failed when converting the varchar value 'null' to data type bit
Could anyone explain what is this for?
This is not in a program.
What you might be trying
INSERT INTO TESTTABLE(BITCOLUMN) VALUES('NULL')
What should it actually be..
INSERT INTO TESTTABLE(BITCOLUMN) VALUES(NULL)
If you want to insert a null value into a column, you need to write NULL, and not 'NULL' (wrapping it in quotes indicates that it is a VARCHAR containing the letters N, U, L L - not a null value).
That is what the error message is telling you: you're trying to insert the VARCHAR value 'NULL' into a column that will only accept bit data.
Change the 'NULL' in your insert query to NULL.
You need something like this:
INSERT INTO TableName(ColumnName) VALUES(NULL); --this is the right way
Instead of this:
INSERT INTO TableName(ColumnName) VALUES('NULL'); --this is the wrong way
Related
I am getting this error
SQL Error: ORA-00928: missing SELECT keyword
00928. 00000 - "missing SELECT keyword"`
when I am trying to insert like this
create table certf
(
certificate_id integer primary key,
certificate_name varchar(100) not null,
certificate_content varchar(300) not null
);
insert into certf (&certificate_id, &certificate_name, &certificate_content);
You are missing values actually:
insert into certf (certificate_id, certificate_name, certificate_content)
values (&certificate_id, &certificate_name, &certificate_content);
Notice that I also added the column list to the insert. This is a best practice.
If those are supposed to be values you're providing as substitution values, then you're missing the values keyword:
insert into certf values (&certificate_id,&certificate_name,&certificate_content);
But you need the string values to be in quotes:
insert into certf values (&certificate_id,'&certificate_name','&certificate_content');
and you should supply the column names too:
insert into certf (certificate_id,certificate_name,certificate_content)
values (&certificate_id,'&certificate_name','&certificate_content');
With you current code the parser is seeing that first list of - possible, but actually invalid in this case - identifiers, i.e column names; because it hasn't seen that values keyword yet. It's treated as something like:
insert into certf (42,some_name,some_content);
And having done that, and when it still doesn't see a values keyword or values list, it's expecting this to be an insert ... select construct instead. You could do it that way:
insert into certf (certificate_id,certificate_name,certificate_content)
select &certificate_id,'&certificate_name','&certificate_content' from dual;
But you aren't doing that. So it doesn't see the select either, and it throws the error you see.
I've got a front table that essentially matches our SSMS database table t_myTable. Some columns I'm having problems with are those with numeric data types in the db. They are set to allow null, but from the front end when the user deletes the numeric value and tries to send a blank value, it's not posting to the database. I suspect because this value is sent back as an empty string "" which does not translate to the null allowable data type.
Is there a trigger I can create to convert these empty strings into null on insert and update to the database? Or, perhaps a trigger would already happen too late in the process and I need to handle this on the front end or API portion instead?
We'll call my table t_myTable and the column myNumericColumn.
I could also be wrong and perhaps this 'empty string' issue is not the source of my problem. But I suspect that it is.
As #DaleBurrell noted, the proper place to handle data validation is in the application layer. You can wrap each of the potentially problematic values in a NULLIF function, which will convert the value to a NULL if an empty string is passed to it.
The syntax would be along these lines:
SELECT
...
,NULLIF(ColumnName, '') AS ColumnName
select nullif(Column1, '') from tablename
SQL Server doesn't allow to convert an empty string to the numeric data type. Hence the trigger is useless in this case, even INSTEAD OF one: SQL Server will check the conversion before inserting.
SELECT CAST('' AS numeric(18,2)) -- Error converting data type varchar to numeric
CREATE TABLE tab1 (col1 numeric(18,2) NULL);
INSERT INTO tab1 (col1) VALUES(''); -- Error converting data type varchar to numeric
As you didn't mention this error, the client should pass something other than ''. The problem can be found with SQL Profiler: you need to run it and see what exact SQL statement is executing to insert data into the table.
I am trying to convert a column formatted in varchar to decimal(19,12) with the following line of code
ALTER TABLE [tablename]
ALTER COLUMN [columnname][format]
and get the following prompt:
Msg 8114, Level 16, State 5, Line 25
Error converting data type varchar to numeric.
Has worked before like a charm. The issue here seems to be that the values in the column are 19 or so digit numeric values formatted as text.
I tried to create a new column, pasted shortened cell values (used the left() function) into it from the original column but that doesn't seem to do the trick either since the code above ends up occationally with the additional "Arithmetic overflow occurred." message.
When some of the rows have incorrect values, ALTER COLUMN would not work. A typical course of action goes like this:
Add a new column of the desired type
Update the column with values that you would like to keep
Drop the old column
Rename the new column
Step 2 would go like this:
UPDATE MyTable
SET NewColumn =
CASE WHEN ISNUMERIC(OldColumn)=1 AND DATALENGTH(OldColumn) <= 19 THEN
CAST(OldColumn AS decimal(19,12))
ELSE
NULL
END
You could also turn ANSI warnings off with SET ANSI_WARNINGS OFF command, which would let you run ALTER COLUMN ignoring data trunction errors. The drawback of this approach is that potential errors get ignored. On the other hand, when you do conversion explicitly with a CASE expression you have an option to supply an alternative value for the error case (I used NULL above, but you can put any number you want).
Could you try to seperate your problem? This does work on SQL 2012:
set nocount on
if object_id ('tempdb..#t1') is not null drop table #t1
create table #t1 (c1 varchar(100))
insert #t1 values ('1234567.8901234567890')
select * from #t1
alter table #t1
alter column c1 decimal(19,12)
select * from #t1
If you play around a bit with the strings you easily can produce an arimetic overflow error. But 'Error converting data type varchar to numeric' needs character or empty sting.
Maybe you can try with your data?
I got the error where my data type is varchar, then I want to insert value/input in textboxt = 'smh85670s'.
It appear to be error. As far as I know varchar can accept characters and numbers, but why does it keep throwing this error?
If I insert value '123456' the table can accept that value.
Please guide me. What data type should I use?
Assuming that you are using Stored procedures (which have an insert query) or directly firing an insert query into DB, you must be sending all data as parameters like say #param1, #param2,...
Your insert query will be like
INSERT INTO Sometable ( Amount, textbox,... )
SELECT #param1, #param2 ,...
Just add a cast in this query to make it work
INSERT INTO Sometable ( Amount, textbox,... )
SELECT #param1, CAST(#param2 as varchar),...
A SAMPLE table has only one column ID of type int, default null.
In Oracle when I do:
insert into SAMPLE (ID) values ('');
the new record is added with blank value. But in SQL Server 2008, when I run the same insert statement, the new record has the value of 0.
Is there a way to force SQL Server 2008 to default blank string to NULL instead of 0 (for numerical type of columns)?
Assuming that your INSERT statement is part of a stored procedure re-used in many places of your application (or, perhaps, is a batch always constructed by the same part of the client code) and that the inserted value is a number passed as a string argument, you could modify the INSERT like this:
INSERT INTO SAMPLE (ID) VALUES (NULLIF(#argument, ''));
Use NULL instead.
insert into SAMPLE (ID) values (NULL);
How about another idea - define an INSTEAD OF INSERT Trigger.
Despite the fact that you're trying to insert a string, with this the operation is "intercepted", empty string is replaced by NULL, and the insert succeeds.
If you define this trigger on your table, then you can continue to insert empty string as before, with no other changes.
Edit: As Martin Smith points out, this effectively is a comparison to 0 (the equivalent of empty string as an int) meaning you won't be able to store 0 in this table. I leave this answer here in case that's acceptable to your situation - either that or re-do all your queries!
CREATE TRIGGER EmptyStringTrigger
ON [SAMPLE]
INSTEAD OF INSERT
AS
BEGIN
INSERT INTO [SAMPLE](ID)
SELECT CASE
WHEN ID = '' THEN NULL
ELSE ID
END
FROM inserted
END
SQL Fiddle example
You can't insert a 'string' into a int column. Oracle must be just handling that for you.
Just try inserting NULL if that's what you need.
insert into SAMPLE (ID) values (NULL);
One more option
insert into SAMPLE (ID) values (DEFAULT)