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Convert a series of parent-child relationships into a hierarchical tree?
... I'd like to turn into as few heirarchical tree structures as possible. So for example, these could be the pairings:
11 Ans...
How do I make and use a Queue in Objective-C?
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I added a commented-out line at the beginning of dequeue for those that wish to return nil rather than raise an exception when trying to dequeue from an empty queue. IMO, following the NSMutableArray behavior of raising an exception is more consistent with Cocoa. After all, you can...
How to add custom method to Spring Data JPA
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You need to create a separate interface for your custom methods:
public interface AccountRepository
extends JpaRepository<Account, Long>, AccountRepositoryCustom { ... }
public interface AccountRepositoryCustom {
public void customMethod();
}
and...
Oracle “Partition By” Keyword
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The PARTITION BY clause sets the range of records that will be used for each "GROUP" within the OVER clause.
In your example SQL, DEPT_COUNT will return the number of employees within that department for every employee record. (It is as if you're de-nomalising the emp table; you still retur...
Where can I find my Facebook application id and secret key?
...ed "My Applications" from which you can select an application to see its information.
You can also go straight here as well, which will list your apps on the left.
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Foreign key constraints: When to use ON UPDATE and ON DELETE
...ve advanced constraints like you would have in postgreSQL but at least the foreign key constraints are quite advanced.
We'll take an example, a company table with a user table containing people from theses company
CREATE TABLE COMPANY (
company_id INT NOT NULL,
company_name VARCHAR(50),
...
Why do I need to override the equals and hashCode methods in Java?
...als(). Failure to do so will result in a violation of the general contract for Object.hashCode(), which will prevent your class from functioning properly in conjunction with all hash-based collections, including HashMap, HashSet, and Hashtable.
Let's try to understand it with an example of what wou...
How do I get textual contents from BLOB in Oracle SQL
...ant to store text in CLOB/NCLOB columns instead of BLOB, which is designed for binary data (your query would work with a CLOB, by the way).
The following query will let you see the first 32767 characters (at most) of the text inside the blob, provided all the character sets are compatible (original...
How to open the Google Play Store directly from my Android application?
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For projects using the Gradle build system, appPackageName is in fact BuildConfig.APPLICATION_ID. No Context/Activity dependencies, reducing the risk of memory leaks.
– Christian García
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jQuery get selected option value (not the text, but the attribute 'value')
...you could use simply this.value to get the selected option value. See demo for more options.
//ways to retrieve selected option and text outside handler
console.log('Selected option value ' + $('select option').filter(':selected').val());
console.log('Selected option value ' + $('select opti...