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@Basic(optional = false) vs @Column(nullable = false) in JPA
...and it turns out the annotation is ignored in actual usage (at least for a String field). (e.g. entityManager.persist calls).
So I went to the specification and read up about it.
Here is what the spec has to say:
http://download.oracle.com/otndocs/jcp/persistence-2.0-fr-oth-JSpec/
Basic(optiona...
What is the difference between save and insert in Mongo DB?
What is the difference between save and insert in Mongo DB?
both looks the same
9 Answers
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How to iterate over a TreeMap? [duplicate]
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Assuming type TreeMap<String,Integer> :
for(Map.Entry<String,Integer> entry : treeMap.entrySet()) {
String key = entry.getKey();
Integer value = entry.getValue();
System.out.println(key + " => " + value);
}
(key and Value typ...
JavaScript .replace only replaces first Match [duplicate]
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Try using a regex instead of a string for the first argument.
"this is a test".replace(/ /g,'%20') // #=> "this%20is%20a%20test"
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ruby operator “=~” [duplicate]
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The =~ operator matches the regular expression against a string, and it returns either the offset of the match from the string if it is found, otherwise nil.
/mi/ =~ "hi mike" # => 3
"hi mike" =~ /mi/ # => 3
"mike" =~ /ruby/ # => nil
You can place the string/regex o...
Android - Round to 2 decimal places [duplicate]
...someone show me how to round double, to get value that I can display as a
String and ALWAYS have 2 decimal places?
2 Answe...
How to convert integer to string in C? [duplicate]
...afer in that you specify how much input you're taking. Otherwise, If your string has multi-byte characters, or ends up longer than you expected due to large numbers, you can overflow your buffer and crash your program (etc).
– gone
Apr 23 '14 at 9:06
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When should I use cross apply over inner join?
...NER JOIN condition.
You could probably do something like that using CTE's and window function:
WITH t2o AS
(
SELECT t2.*, ROW_NUMBER() OVER (PARTITION BY t1_id ORDER BY rank) AS rn
FROM t2
)
SELECT t1.*, t2o.*
FROM t1
INNER JOIN
t2o
ON t2o.t1...
awk without printing newline
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Minor note: never use printf $0, since $0 may contain strings like %F, etc... Following easily fails (at least with GAWK 3.1.5): echo "%F"|awk '{printf $0}'. Use the printf "%s",$0 instead.
– Vlad
Dec 21 '16 at 5:51
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How to catch SQLServer timeout exceptions
...ntly. I know I could catch the SqlException and then check if the message string Contains "Timeout" but was wondering if there is a better way to do it?
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