Tag Archives: java

MYSQL: Get the Auto-Increment Values after Insert Statement

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Until sometime back, I was unaware of how I could get the value of an auto-incremented field after an Insert Statement. But recently I needed it for two of my projects simultaneously, so I explored the possibilities. As one of my project is in Java and other is in PHP, we will go through both of them.

So, here is the problem. In general, the PRIMARY KEY field is the AUTO_INCREMENT field. Now wen you insert a row, a new key is generated and you can’t get it through usual way as this row can be accessed only using the primary key.

So here is how it can be done:
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Sorting a 2-Dimensional Array in Java

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Recently while working for my project, I came across this situation when I had a 2-D array and I needed to sort it twice on 2 of its columns. Consider the following 2D array:

String[][] testString = new String[][] {
    {"1", "2", "6"},
    {"4", "5", "3"}
  };

Sorting the above 2D array on zero column will give

{
    {"1", "2", "6"},
    {"4", "5", "3"}
}

whereas sorting it on second column will give

{
    {"4", "5", "3"},
    {"1", "2", "6"}
}

I did not want to do the most common as well as tedious thing, i.e. write my own sorting function like this:

public void myOwnSort(String [][] exampleArray) {
    //code for sorting the array according to my wish.
}

I wanted to avoid this for 2 resons:

  1. I would have to write the code for it ( lazy me!!).
  2. Secondly, I can possibly never match the efficiency provided by the sorting functions of java.util.Arrays

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