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jQuery - selecting elements from inside a element

... Actually, $('#id', this); would select #id at any descendant level, not just the immediate child. Try this instead: $(this).children('#id'); or $("#foo > #moo") or $("#foo > span") ...
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SQL - HAVING vs. WHERE

...ows; HAVING clause introduces a condition on aggregations, i.e. results of selection where a single result, such as count, average, min, max, or sum, has been produced from multiple rows. Your query calls for a second kind of condition (i.e. a condition on an aggregation) hence HAVING works correctl...
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Adding options to a using jQuery?

... This did NOT work in IE8 (yet did in FF): $("#selectList").append(new Option("option text", "value")); This DID work: var o = new Option("option text", "value"); /// jquerify the DOM object 'o' so we can use the html method $(o).html("option text"); $("#selectList").a...
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What is the 'instanceof' operator used for in Java?

...cked state. Instead, you'd see if each object is a checkbox, and if it is, cast it to a checkbox and check its properties. if (obj instanceof Checkbox) { Checkbox cb = (Checkbox)obj; boolean state = cb.getState(); } ...
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structure vs class in swift language

... provide access to their variables Only class can do: Inheritance Type casting Define deinitialisers Allow reference counting for multiple references. share | improve this answer | ...
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Convert a byte array to integer in Java and vice versa

...y. Before you performing & operation on byte with 0xFF (int), JVM will cast the byte to int with 1 extended or 0 extended according the the leading bit first. There's no unsigned byte in Java, bytes are always signed. – Nier Mar 24 '16 at 3:35 ...
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Find rows that have the same value on a column in MySQL

...sses and how many times they're used, with the most used addresses first. SELECT email, count(*) AS c FROM TABLE GROUP BY email HAVING c > 1 ORDER BY c DESC If you want the full rows: select * from table where email in ( select email from table group by email having count(*) &g...
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What exactly do “IB” and “UB” mean?

...by the compiler writers. An example of this is the result of a reinterpret_cast. usually, it simply changes the type of a pointer, without modifying the address, but the mapping is actually implementation-defined, so a compiler could map to a completely different address, as long as it documented th...
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Select multiple columns in data.table by their numeric indices

How can we select multiple columns using a vector of their numeric indices (position) in data.table ? 5 Answers ...
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Why is super.super.method(); not allowed in Java?

...hat you can access shadowed variables from superclasses of superclasses by casting this: interface I { int x = 0; } class T1 implements I { int x = 1; } class T2 extends T1 { int x = 2; } class T3 extends T2 { int x = 3; void test() { System.out.println("x=\t\t" ...