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What's the difference between @JoinColumn and mappedBy when using a JPA @OneToMany association
...t this entity is the owner of the relationship (that is: the corresponding table has a column with a foreign key to the referenced table), whereas the attribute mappedBy indicates that the entity in this side is the inverse of the relationship, and the owner resides in the "other" entity. This also ...
Is SHA-1 secure for password storage?
...ht now even with the "broken" hash functions MD5 and SHA-1.
About rainbow tables:
The "rainbow attack" is actually cost-sharing of a dictionary or brute force attack. It is a derivative from the time-memory trade-off first described by Hellman in 1980. Assuming that you have N possible passwords (...
What are the differences between a clustered and a non-clustered index?
...
Clustered Index
Only one per table
Faster to read than non clustered as data is physically stored in index order
Non Clustered Index
Can be used many times per table
Quicker for insert and update operations than a clustered index
Both types of inde...
What is the relative performance difference of if/else versus switch statement in Java?
...ere are more than two if/else blocks glued together or its size is unpredictable, then you may highly consider a switch statement.
Alternatively, you can also grab Polymorphism. First create some interface:
public interface Action {
void execute(String input);
}
And get hold of all implemen...
Preventing Laravel adding multiple records to a pivot table
...in the array. This way, only the id's given in the array will exist in the table. Brilliant @Barryvdh uses an undocumented second parameter to disable that detaching, so no relationships not in the given array are deleted but only unique id's will be attached. Check out the "syncing for convienence"...
How can I get the SQL of a PreparedStatement?
...ke this:
org.hsqldb.jdbc.JDBCPreparedStatement@7098b907[sql=[INSERT INTO
TABLE_NAME(COLUMN_NAME, COLUMN_NAME, COLUMN_NAME) VALUES(?, ?, ?)],
parameters=[[value], [value], [value]]]
Now I've created a method (Java 8), which is using regex to extract both query and values and put them into map:
p...
assertEquals vs. assertEqual in python
...ase methods had one or more aliases that are now deprecated. The following table lists the correct names along with their deprecated aliases:
Method Name | Deprecated alias | Deprecated alias
--------------+------------------+-----------------
assertEqual() | failUnlessEqual | assertEquals
...
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Oracle find a constraint
...stem generated constraint name. For instance, if we specify NOT NULL in a table declaration. Or indeed a primary or unique key. For example:
SQL> create table t23 (id number not null primary key)
2 /
Table created.
SQL> select constraint_name, constraint_type
2 from user_constraint...
How to select multiple rows filled with constants?
Selecting constants without referring to a table is perfectly legal in an SQL statement:
15 Answers
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Nested Models in Backbone.js, how to approach
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Of course, if you want to go as far as saving the nested model in its own table. This wouldn't be sufficient. But in the case of reading and saving the object as a whole, this solution should suffice.
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