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Converting JSON data to Java object
...s from a JSON string within my Java action method. The string is available by simply saying myJsonString = object.getJson() . Below is an example of what the string can look like:
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SQL SELECT speed int vs varchar
...e space usage of different date types:
int fields occupy between 2 and 8 bytes, with 4 being usually more than enough ( -2147483648 to +2147483647 )
character types occupy 4 bytes plus the actual strings.
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How to use querySelectorAll only for elements that have a specific attribute set?
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@blackHawk The syntax uses CSS Selectors. As specified by MDN it "is a string containing one or more CSS selectors separated by commas". You can read about CSS Selectors here.
– martieva
Oct 21 '16 at 14:52
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How to check existence of user-define table type in SQL Server 2008?
...using type_id won't verify that the type is a table type--just that a type by that name exists. Otherwise gbn's query is probably better.
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What is the “N+1 selects problem” in ORM (Object-Relational Mapping)?
... @ariel The 'correct' way is to get all the wheels, ordered by CarId (1 select), and if more details than the CarId are required, make a second query for all cars (2 queries total). Printing things out is now optimal, and no indexes or secondary storage were required (you can iterate ...
Why do I need to override the equals and hashCode methods in Java?
...l if their importantField is equal (with hashCode() and equals() generated by eclipse)
public class MyClass {
private final String importantField;
private final String anotherField;
public MyClass(final String equalField, final String anotherField) {
this.importantField = equal...
SQL Group By with an Order By
...ersions of MySQL, simply alias the aggregate in the SELECT list, and order by the alias:
SELECT COUNT(id) AS theCount, `Tag` from `images-tags`
GROUP BY `Tag`
ORDER BY theCount DESC
LIMIT 20
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How to store arrays in MySQL?
...o be stored in the third table? Can I just do a query to find the relation by just storing the primary keys from two tables?
– tonga
Jun 28 '13 at 19:20
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Find rows that have the same value on a column in MySQL
...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(*) > 1
)
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How to handle many-to-many relationships in a RESTful API?
...you can return documents that describe the relationships between resources by encoding those relationships as links. Thus, a team can be said to have a document resource (/team/{id}/players) that is a list of links to players (/player/{id}) on the team, and a player can have a document resource (/pl...