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How to remove all null elements from a ArrayList or String Array?
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Try:
tourists.removeAll(Collections.singleton(null));
Read the Java API. The code will throw java.lang.UnsupportedOperationException for immutable lists (such as created with Arrays.asList); see this answer for more details.
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Ternary Operator Similar To ?:
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answered Feb 9 '11 at 16:45
Rex KerrRex Kerr
160k2323 gold badges302302 silver badges398398 bronze badges
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How do I find a default constraint using INFORMATION_SCHEMA?
...efault value constraint
SELECT
default_constraints.name
FROM
sys.all_columns
INNER JOIN
sys.tables
ON all_columns.object_id = tables.object_id
INNER JOIN
sys.schemas
ON tables.schema_id = schemas.schema_id
INNER JOIN
sys.default_const...
Explicitly set Id with Doctrine when using “AUTO” strategy
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New solution works fine only when ALL entities have id before insert. When one entity has ID and another one does not - new solution is failing.
I use this function for import all my data:
function createEntity(\Doctrine\ORM\EntityManager $em, $entity, $id ...
Merge 2 arrays of objects
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answered Jun 3 '16 at 6:14
Jahanzaib AslamJahanzaib Aslam
1,95011 gold badge1717 silver badges2222 bronze badges
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How to get a list of column names on Sqlite3 database?
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PRAGMA table_info(table_name);
will get you a list of all the column names.
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Get underlying NSData from UIImage
...e share ;)
– tybro0103
Mar 6 '14 at 16:16
@1dayitwillmake Even the PNG rep? Not my area of expertise, but I thought PN...
Find integer index of rows with NaN in pandas dataframe
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And just in case, if you want to find the coordinates of 'nan' for all the columns instead (supposing they are all numericals), here you go:
df = pd.DataFrame([[0,1,3,4,np.nan,2],[3,5,6,np.nan,3,3]])
df
0 1 2 3 4 5
0 0 1 3 4.0 NaN 2
1 3 5 6 NaN 3.0 3
np.where(np.as...
How do I find the .NET version?
How do I find out which version of .NET is installed?
19 Answers
19
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Nullable Foreign Key bad practice?
... read.
Only if you know better than Chris Date "what first normal form really means". If x and y are both nullable, and indeed in some row x and y are both null, then WHERE x=y does not yield true. This proves beyond reasonable doubt that null is not a value (because any real value is always equ...