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How to get the first non-null value in Java?
Is there a Java equivalent of SQL's COALESCE function? That is, is there any way to return the first non-null value of several variables?
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Check if value exists in Postgres array
...a subquery, for instance) or an array. There are several ways to use it:
SQLAlchemy: how to filter on PgArray column types?
IN vs ANY operator in PostgreSQL
Important difference: Array operators (<@, @>, && et al.) expect array types as operands and support GIN or GiST indices in t...
Should I add the Visual Studio .suo and .user files to source control?
... I believe it stores the debug info in the .user file (at least for SQL Server Data Tools). Also, when you change the settings in the Debug tab, it's not always persisted to .user straight away (closing the solution seems to work, bit annoying... or changing another setting stored in the .sql...
Build an ASCII chart of the most commonly used words in a given text [closed]
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Transact SQL set based solution (SQL Server 2005) 1063 892 873 853 827 820 783 683 647 644 630 characters
Thanks to Gabe for some useful suggestions to reduce the character count.
NB: Line breaks added to avoid scrollbars only the l...
What is the string length of a GUID?
I want to create a varchar column in SQL that should contain N'guid' while guid is a generated GUID by .NET ( Guid.NewGuid ) - class System.Guid.
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How to retrieve the current value of an oracle sequence without increment it?
Is there an SQL instruction to retrieve the value of a sequence that does not increment it.
6 Answers
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What is the benefit of zerofill in MySQL?
... what is the benefit/usage of defining ZEROFILL for INT DataType in MySQL ?
9 Answers
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When and why JPA entities should implement Serializable interface?
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This usually happens if you mix HQL and native SQL queries. In HQL, Hibernate maps the types you pass in to whatever the DB understands. When you run native SQL, then you must do the mapping yourself. If you don't, then the default mapping is to serialize the parameter an...
How do I do a not equal in Django queryset filtering?
... import Lookup
class NotEqual(Lookup):
lookup_name = 'ne'
def as_sql(self, qn, connection):
lhs, lhs_params = self.process_lhs(qn, connection)
rhs, rhs_params = self.process_rhs(qn, connection)
params = lhs_params + rhs_params
return '%s <> %s' % (lhs,...
Include headers when using SELECT INTO OUTFILE?
Is it possible to include the headers somehow when using the MySQL INTO OUTFILE ?
18 Answers
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