There is no difference, they do the same thing. 

    CREATE TRIGGER trgTable on dbo.Table FOR INSERT,UPDATE,DELETE

Is the same as


    CREATE TRIGGER trgTable on dbo.Table AFTER INSERT,UPDATE,DELETE


An `INSTEAD OF` trigger is different, and fires before and instead of the insert and can be used on views, in order to insert the appropriate values into the underlying tables.

[@Ben][1] is absolutely right.

Here is MSDN article [Exploring SQL Server Triggers][2]

A paragraph from the article:

&gt; That syntax is also acceptable in older versions of SQL Server. However, now that there are two types of triggers in SQL Server 2000, **I prefer to refer to FOR triggers as AFTER triggers. Thus, for the remainder of this article I will refer to either AFTER or INSTEAD OF triggers.**
&gt;
&gt; Like the AFTER trigger you saw earlier, this trigger prevents changes from being made to the lastname field. However, it implements this business rule differently than the previous example. Because the INSTEAD OF trigger fires in place of the UPDATE statement, the INSTEAD OF trigger then evaluates if the business rule test passes or not. If the business rule test passes, in order for the update to occur the INSTEAD OF trigger must explicitly invoke the UPDATE statement again.

  [1]: https://stackoverflow.com/a/5340728
  [2]: https://web.archive.org/web/20130101145248/http://msdn.microsoft.com/en-gb/magazine/cc164047.aspx

AFTER specifies that the DML trigger is fired only when all operations specified in the triggering SQL statement have executed successfully. All referential cascade actions and constraint checks also must succeed before this trigger fires. 
AFTER is the default when FOR is the only keyword specified. 

AFTER triggers cannot be defined on views. 

INSTEAD OF
Specifies that the DML trigger is executed instead of the triggering SQL statement, therefore, overriding the actions of the triggering statements. INSTEAD OF cannot be specified for DDL or logon triggers. 

[https://docs.microsoft.com/en-us/sql/t-sql/statements/create-trigger-transact-sql][1]


  [1]: https://docs.microsoft.com/en-us/sql/t-sql/statements/create-trigger-transact-sql

I&#39;m trying to write code to read a binary file into a buffer, then write the buffer to another file.  I have the following code, but the buffer only stores a couple of ASCII characters from the first line in the file and nothing else.

    int length;
    char * buffer;
    
    ifstream is;
    is.open (&quot;C:\\Final.gif&quot;, ios::binary );
    // get length of file:
    is.seekg (0, ios::end);
    length = is.tellg();
    is.seekg (0, ios::beg);
    // allocate memory:
    buffer = new char [length];
    // read data as a block:
    is.read (buffer,length);
    is.close();
     
    FILE *pFile;
    pFile = fopen (&quot;C:\\myfile.gif&quot;, &quot;w&quot;);
    fwrite (buffer , 1 , sizeof(buffer) , pFile );

Reading and writing binary file

I need to split a String into an array of single character Strings.

Eg, splitting &quot;cat&quot; would give the array &quot;c&quot;, &quot;a&quot;, &quot;t&quot;

Split string into array of character strings

What&#39;s the difference between `FOR` and `AFTER` triggers?

Difference between FOR and AFTER triggers?

<p>What's the difference between <code>FOR</code> and <code>AFTER</code> triggers?</p>


I would like to force the auto increment field of a table to some value, I tried with this:

    ALTER TABLE product AUTO_INCREMENT = 1453

AND 

    ALTER SEQUENCE product  RESTART WITH 1453;
    ERROR:  relation &quot;your_sequence_name&quot; does not exist

I&#39;m new to postgres :( 

I have a table `product` with `Id` and `name` field



Reset auto increment counter in postgres

I had an assignment for each table to count nullable columns. Easy:

     SELECT table_name, count(*) FROM INFORMATION_SCHEMA.COLUMNS
     WHERE is_nullable=&#39;NO&#39;
     GROUP BY table_name;
&lt;br&gt;
Now I have to modify this to count &quot;columns that have property &quot;NOT NULL&quot;&quot;. Will the following code do this or will it just check weather column name is not null?

    CREATE TEMP TABLE A AS 
    SELECT DISTINCT column_name, table_name AS name FROM INFORMATION_SCHEMA.COLUMNS
    WHERE column_name IS NOT NULL
    GROUP BY table_name, column_name;
    
    SELECT name, count(*) FROM A
    GROUP BY name;

If no... Any advices?

Finding columns that are NOT NULL in PostgreSQL

I&#39;m using PostgreSQL and I&#39;m trying to list all the tables that have a particular column from a table as a foreign-key/reference. Can this be done? I&#39;m sure this information is stored somewhere in `information_schema` but I have no idea how to start querying it.

PostgreSQL: SQL script to get a list of all tables that have a particular column as foreign key

I would like to convert this SQL statement to a JPQL equivalent.

    SELECT * FROM events
    WHERE events_date BETWEEN &#39;2011-01-01&#39; AND &#39;2011-03-31&#39;;

This correctly retrieves the information from the table `events`.

In my `Events` entity     

       @Column(name = &quot;events_date&quot;)  
       @Temporal(TemporalType.DATE)  
       private Date eventsDate;

So far this is what I have but it is not working.

    public List&lt;Events&gt; findAllEvents(Date startDate, Date endDate) {    
      List&lt;Events&gt; allEvents = entityManager.createQuery(
        &quot;SELECT e FROM Events e WHERE t.eventsDate BETWEEN :startDate AND :endDate&quot;)  
      .setParameter(&quot;startDate&quot;, startDate, TemporalType.DATE)  
      .setParameter(&quot;endDate&quot;, endDate, TemporalType.DATE)  
      .getResultList();
      return allEvents ;  
    }

What am I doing wrong? Thanks.

JPQL SELECT between date statement

OK I tried googling for an answer like crazy, but I couldn&#39;t resolve this, so I hope someone will be able to help.

Let&#39;s say I have a table of users, very simple table:

    id | userName
    3    Michael
    4    Mike
    5    George

and I have another table of their cars and their prices.

    id | belongsToUser | carPrice
    1    4               5000
    2    4               6000
    3    4               8000

Now what I need to do is something like this (feel free to rewrite):

       SELECT
          `userName`,
          `carPrice`
       FROM `users`
       LEFT JOIN `cars`
       ON cars.belongsToUser=users.id
       WHERE `id`=&#39;4&#39;

Which returns:

    Mike | 5000

But I need the most expensive car of a certain user, not the first entry found.

So question: How do I set the LEFT JOIN table to be ordered by carPrice, DESC ?

how to sort order of LEFT JOIN in SQL query?

In both queries 1 and 2, the text from the textbox is inserted into the database. What&#39;s the significance of the parameterized query here?

1. Passing `txtTagNumber` as a query parameter

        SqlCommand cmd = new SqlCommand(&quot;INSERT INTO dbo.Cars &quot; +&quot;VALUES(@TagNbr);&quot; , conn);
        cmd.Parameters.Add(&quot;@TagNbr&quot;, SqlDbType.Int);
        cmd.Parameters[&quot;@TagNbr&quot;].Value = txtTagNumber.Text;

3. Converting `txtTagNumber` to an integer before constructing the query

        int tagnumber = txtTagNumber.Text.ToInt16(); /* EDITED */
        INSERT into Cars values(tagnumber.Text); /* then is it the same? */

Also, here I would use Regular Expression validation to stop insertion of illegal characters.




How do parameterized queries help against SQL injection?

We are using ASP.NET (Framework 2) and setting database connection strings (SQL2005) in web.config.

We are currently using &quot;`providerName=SqlServer`&quot;.

All our data accesses are done using `System.Data.SqlClient` - should we therefore change to `providerName=System.Data.SqlClient`? I find many examples of this providerName on the web, but very little explaining what providerName=SqlServer actually means.

Is there a difference? I&#39;m worried that the providerName we currently specify is actually referencing a legacy (and maybe slower) client, or is there an even more efficient client than SqlClient for use with ASP.NET?

SQL providerName in web.config

I have the following:

    CREATE NONCLUSTERED INDEX [MyTableIndex]
    ON [dbo].[tablename] ([tablename_ID],[tablename_Field1])
    INCLUDE ([Tablename_Field2],[Tablename_Field3])

I want to create an if statement to check if this exists. How do I do this?


How do I check if a nonclustered index exists in SQL Server 2005

I am trying to order by date. I want the most recent dates coming in first. That&#39;s easy enough, but there are many records that are null and those come before any records that have a date.

I have tried a few things with no success:

    ORDER BY ISNULL(Next_Contact_Date, 0)
    
    ORDER BY ISNULL(Next_Contact_Date, 999999999)
    
    ORDER BY coalesce(Next_Contact_Date, 99/99/9999)

How can I order by date and have the nulls come in last? The data type is `smalldatetime`.

SQL Server ORDER BY date and nulls last

How do I query DateTime database field within a certain range?

I am using SQL SERVER 2005

Error code below

    SELECT * 
      FROM TABLENAME 
     WHERE DateTime &gt;= 12/04/2011 12:00:00 AM 
       AND DateTime &lt;= 25/05/2011 3:53:04 AM

Note that I need to get rows within a certain time range.  Example, 10 mins time range.

Currently SQL return with Incorrect syntax near &#39;12&#39;.&quot;

Simple DateTime sql query

What is the easiest and best way to trigger **change** event when setting the value of **select** element.

I&#39;ve expected that executing the following code

    $(&#39;select#some&#39;).val(10);

or

    $(&#39;select#some&#39;).attr(&#39;value&#39;,  10);

would result in triggering the change event, which i think is pretty logic thing to be done. Right?

Well, it isn&#39;t the case. You need to triger change() event by doing this

    $(&#39;select#some&#39;).val(10).change();

or

    $(&#39;select#some&#39;).val(10).trigger(&#39;change&#39;);

but i&#39;m looking for some solution which would trigger change event as soon as select&#39;s value is changed by some javascript code.



Trigger change() event when setting &lt;select&gt;&#39;s value with val() function

I have a link:

    &lt;ul id=&quot;titleee&quot; class=&quot;gallery&quot;&gt;
      &lt;li&gt;
        &lt;a href=&quot;#inline&quot; rel=&quot;prettyPhoto&quot;&gt;Talent&lt;/a&gt;
      &lt;/li&gt;
    &lt;/ul&gt;

and I am trying to trigger it by using:

    $(document).ready(function() {
      $(&#39;#titleee&#39;).find(&#39;a&#39;).trigger(&#39;click&#39;);
    });

But it doesn&#39;t work.

I&#39;ve also tried: `$(&#39;#titleee a&#39;).trigger(&#39;click&#39;);`

**Edit**:

I actually need to trigger whatever get&#39;s called here `&lt;a href=&quot;#inline&quot; rel=&quot;prettyPhoto&quot;&gt;`

How to trigger a click on a link using jQuery

Is there any possibility to use an &quot;after update&quot; trigger only in the case the data has been REALLY changed.
I know of &quot;NEW and OLD&quot;. But when using them I&#39;m only able to compare columns.
For example &quot;NEW.count &lt;&gt; OLD.count&quot;.

But I want something like: run trigger if &quot;NEW &lt;&gt; OLD&quot;

An Example:

    create table foo (a INT, b INT);
    create table bar (a INT, b INT);

    INSERT INTO foo VALUES(1,1);
    INSERT INTO foo VALUES(2,2);
    INSERT INTO foo VALUES(3,3);

    CREATE TRIGGER ins_sum
        AFTER UPDATE ON foo
        FOR EACH ROW
        INSERT INTO bar VALUES(NEW.a, NEW.b);

    UPDATE foo SET b = 3 WHERE a=3;
    Query OK, 0 rows affected (0.00 sec)
    Rows matched: 1  Changed: 0  Warnings: 0


    select * from bar;
    +------+------+
    | a    | b    |
    +------+------+
    |    3 |    3 |
    +------+------+

The point is, there was an update, but **nothing has changed**.
But the trigger ran anyway. IMHO there should be a way it doesn&#39;t.

I know that I could have used 

&gt; IF NOW.b &lt;&gt; OLD.b

for this example.

BUT imagine a large table with changing columns.
You have to compare every column and if the database changes you have to adjust the trigger.
AND it doesn&#39;t &quot;feel&quot; good to compare every column of the row hardcoded :)

**Addition**

As you can see on the line 

&gt; Rows matched: 1  Changed: 0  Warnings: 0

MySQL knows that the line didn&#39;t change. But it doesn&#39;t share this knowledge with the trigger.
A trigger like &quot;AFTER REAL UPDATE&quot; or something like this would be cool.


MySQL Trigger after update only if row has changed

    class TodoList(models.Model):
        title = models.CharField(maxlength=100)
        slug = models.SlugField(maxlength=100)
        def save(self):
            self.slug = title
            super(TodoList, self).save()

I&#39;m assuming the above is how to create and store a slug when a title is inserted into the table TodoList, if not, please correct me!

Anyhow, I&#39;ve been looking into pre_save() as another way to do this, but can&#39;t figure out how it works.  How do you do it with pre_save()?

is it like

    def pre_save(self):
         self.slug = title

I&#39;m guessing no.  What is the code to do this?

Thanks!

Populating django field with pre_save()?

They seem the same. Is there a significant difference? I think I am missing something.

Content Type	Original Author	Original Content on Stackoverflow
Question	sqlchild	View Question on Stackoverflow
Solution 1 - Sql	Ben	View Answer on Stackoverflow
Solution 2 - Sql	Waqas Raja	View Answer on Stackoverflow
Solution 3 - Sql	Nour El-Hoda	View Answer on Stackoverflow

Difference between FOR and AFTER triggers?

Sql Problem Overview

Sql Solutions

Solution 1 - Sql

Solution 2 - Sql

Solution 3 - Sql

Split string into array of character strings

Reading and writing binary file

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