This tag refers to an object or type that is not null (none).
Use this tag for questions related to not-null types or objects (i.e. detecting them, handling them, etc.).
Questions tagged [notnull]
295 questions
320
votes
10 answers
MySQL SELECT only not null values
Is it possible to do a select statement that takes only NOT NULL values?
Right now I am using this:
SELECT * FROM table
And then I have to filter out the null values with a php loop.
Is there a way to do:
SELECT * (that are NOT NULL) FROM…
bryan sammon
- 7,161
- 15
- 38
- 48
213
votes
17 answers
How do I check if a SQL Server text column is empty?
I am using SQL Server 2005. I have a table with a text column and I have many rows in the table where the value of this column is not null, but it is empty. Trying to compare against '' yields this response:
The data types text and varchar are…
atoumey
- 2,536
- 2
- 20
- 16
178
votes
8 answers
insert a NOT NULL column to an existing table
I have tried:
ALTER TABLE MY_TABLE
ADD STAGE INT NOT NULL;
But it gives this error message:
ALTER TABLE only allows columns to be added that can contain nulls or
have a DEFAULT definition specified
ANP
- 15,287
- 22
- 58
- 79
150
votes
1 answer
Why does the C# compiler translate this != comparison as if it were a > comparison?
I have by pure chance discovered that the C# compiler turns this method:
static bool IsNotNull(object obj)
{
return obj != null;
}
…into this CIL:
.method private hidebysig static bool IsNotNull(object obj) cil managed
{
ldarg.0 // obj
…
stakx - no longer contributing
- 83,039
- 20
- 168
- 268
148
votes
5 answers
Ruby on Rails: How do I add a not null constraint to an existing column using a migration?
In my Rails (3.2) app, I have a bunch of tables in my database but I forgot to add a few not null constraints. How can I write a migration which adds not null to an existing column?
David Robertson
- 1,809
- 3
- 12
- 12
101
votes
6 answers
How to drop all NOT NULL constraints from a PostgreSQL table in one go
Is it possible to drop all NOT NULL constraints from a table in one go?
I have a big table with a lot of NOT NULL constraints and I'm searching for a solution that is faster than dropping them separately.
Stefan
- 1,383
- 2
- 15
- 25
60
votes
4 answers
Not annotated method overrides method annotated with @NotNull
I'm implementing a custom data structure that gives me some properties of sets and other properties of lists. For most of the implemented methods though, I get this weird warning in IntelliJ IDEA on Java 7:
Not annotated method overrides method…
BrDaHa
- 5,138
- 5
- 32
- 47
48
votes
6 answers
How to ignore null values using springframework BeanUtils copyProperties?
I would like to know how to copy the properties from an Object Source to an Object Dest ignoring null values using Spring Framework.
I actually use Apache beanutils, with this code
beanUtils.setExcludeNulls(true);
…
Fingolricks
- 1,196
- 2
- 14
- 30
41
votes
4 answers
Hibernate @NotEmpty annotation equivalent in Javax.package or alternative
Is there a way to implement @NotEmpty hibernate validation without writing custom validation?
javax.validation package does not contain this annotation. Only @NotNull. But it does not validate for Non-null but empty values. So I would like to see an…
Kevin Rave
- 13,876
- 35
- 109
- 173
34
votes
4 answers
Sql Conditional Not Null Constraint
I am curious to know is it possible to create a conditional not null constraint in sql? In otherwords is it possible to create a constraint such that a column B can be null as long column A contains lets say 'NEW' but if the contents of column A…
Heinrich
- 2,144
- 3
- 23
- 39
32
votes
5 answers
Alter column default value
I know you can change the default value of an existing column like this:
ALTER TABLE Employee ADD CONSTRAINT DF_SomeName DEFAULT N'SANDNES' FOR CityBorn;
But according to this my query supposed to work:
ALTER TABLE MyTable ALTER COLUMN CreateDate…
SZT
- 1,771
- 4
- 26
- 53
28
votes
2 answers
MySQL - How Do I Count Nulls and Not Nulls?
I have a simple table of installs:
prod_code
email
install_slot
If the install_slot is NULL, then it's an available install slot. Not null -- then, used slot. I need to return a result of total installs for a given product and email, as well as a…
Volomike
- 23,743
- 21
- 113
- 209
28
votes
3 answers
Alter column set not null fails
Consider the following table with approximately 10M rows
CREATE TABLE user
(
id bigint NOT NULL,
...
CONSTRAINT user_pk PRIMARY KEY (id)
)
WITH (
OIDS=FALSE
)
Then i applied the following alter
ALTER TABLE USER ADD COLUMN BUSINESS_ID …
dimcookies
- 1,930
- 7
- 31
- 37
25
votes
1 answer
Not annotated parameter overrides @??? parameter
While overriding code:
@Override
public void open(ExecutionContext executionContext) {
super.open(executionContext);
from: org.springframework.batch.item.support.AbstractItemCountingItemStreamItemReader
I received an IntelliJ…
DerBenniAusA
- 727
- 1
- 7
- 13
24
votes
2 answers
Check a record IS NOT NULL in plsql
I have a function which would return a record with type my_table%ROWTYPE, and in the caller, I could check if the returned record is null, but PL/SQL complains the if-statement that
PLS-00306: wrong number or types of arguments in call to 'IS NOT…
Sapience
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