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Group by month and year in MySQL
Given a table with a timestamp on each row, how would you format the query to fit into this specific json object format.
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LEN function not including trailing spaces in SQL Server
I have the following test table in SQL Server 2005:
10 Answers
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Difference between @OneToMany and @ElementCollection?
...ring> strings;
Simpler, isn't it? Note that you can still control the table and column names using @CollectionTable annotation.
See also:
Java Persistence/ElementCollection
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Update a column value, replacing part of a string
I have a table with the following columns in a MySQL database
6 Answers
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What's wrong with using == to compare floats in Java?
...lse ensure that no float which compares unequal to itself gets stored in a table. Otherwise, a program which tries to e.g. count how many unique results can be produced from an expression when fed various inputs may regard every NaN value as unique.
– supercat
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Checking if a SQL Server login already exists
...ction. Attacker can pass a @loginName like x] with password ''y'';\r\ndrop table foo;\r\n
– Remus Rusanu
Sep 4 '09 at 14:47
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Converting file size in bytes to human-readable string
...r, and Diff. The cleanup operation resulted in the growth of some database tables, and the reduction in others. For example, Table A has a diff of -1.95 MB, while Table B has a diff of 500 kB. Therefore: positive and negative :-)
– Aaron Blenkush
May 2 '14 at 1...
Which @NotNull Java annotation should I use?
...nt approaches. Some packages use JLS 9.6.4.1 style contexts. The following table gives an overview:
FIELD METHOD PARAMETER LOCAL_VARIABLE
android.support.annotation X X X
edu.umd.cs.findbugs.annotations X X X X
org.jetbra...
The case against checked exceptions
...with it.
This would be clearer with a counter-case. Imagine I'm writing a table API. I have the table model somewhere with an API including this method:
public RowData getRowData(int row)
Now as an API programmer I know there will be cases where some client passes in a negative value for the ro...
Why are ToLookup and GroupBy different?
...happens when you call ToLookup on an object representing a remote database table with a billion rows in it?
The billion rows are sent over the wire, and you build the lookup table locally.
What happens when you call GroupBy on such an object?
A query object is built; end of story.
When that quer...