[CHARINDEX][1] is what you are looking for

    select CHARINDEX(&#39;@&#39;, &#39;someone@somewhere.com&#39;)
    -----------
    8
    
    (1 row(s) affected)

-or-

    select CHARINDEX(&#39;c&#39;, &#39;abcde&#39;)
    -----------
    3
    
    (1 row(s) affected)


  [1]: http://msdn.microsoft.com/en-us/library/ms186323.aspx


You can use either [CHARINDEX][1] or [PATINDEX][2] to return the starting position of the specified expression in a character string.

    CHARINDEX(&#39;bar&#39;, &#39;foobar&#39;) == 4
    PATINDEX(&#39;%bar%&#39;, &#39;foobar&#39;) == 4

Mind that you need to use the wildcards in PATINDEX on either side.

  [1]: http://msdn.microsoft.com/en-us/library/ms186323%28SQL.90%29.aspx
  [2]: http://msdn.microsoft.com/en-us/library/ms188395%28SQL.90%29.aspx

One very small nit to pick:

The RFC for email addresses allows the first part to include an &quot;@&quot; sign if it is quoted. Example:

    &quot;john@work&quot;@myemployer.com

This is quite uncommon, but could happen. Theoretically, you should split on the *last* &quot;@&quot; symbol, not the first:

    SELECT LEN(EmailField) - CHARINDEX(&#39;@&#39;, REVERSE(EmailField)) + 1

More information:

http://en.wikipedia.org/wiki/Email_address

I believe you want to use `CHARINDEX`. You can read about it [here][1].


  [1]: http://msdn.microsoft.com/en-us/library/ms186323.aspx

Given 2 angles in the range -PI -&gt; PI around a coordinate, what is the value of the smallest of the 2 angles between them?

Taking into account that the difference between PI and -PI is not 2 PI but zero.

**Example:**

Imagine a circle, with 2 lines coming out from the center, there are 2 angles between those lines, the angle they make on the inside aka **the smaller angle**, and the angle they make on the outside, aka the bigger angle. Both angles when added up make a full circle. Given that each angle can fit within a certain range, **what is the smaller angles value, taking into account the rollover**

How can I find the difference between two angles?

I need to iterate through a `DataTable`. I have an column there  named `ImagePath`.

When I am using `DataReader` I do it this way:

    SqlDataReader dr = null;
    dr = cmd.ExecuteReader();
    while (dr.Read())
    {
        TextBox1.Text = dr[&quot;ImagePath&quot;].ToString();
    }

How can I achieve the same thing using `DataTable`?


How to iterate through a DataTable

Given an email address column, I need to find the position of the @ sign for substringing.

What is the `indexof` function, for strings in T-SQL?

Looking for something that returns the position of a substring within a string.

in C#

&lt;!-- language: c# --&gt;

    var s = &quot;abcde&quot;;
    s.IndexOf(&#39;c&#39;); // yields 2


IndexOf function in T-SQL

Given an email address column, I need to find the position of the @ sign for substringing.
What is the <code>indexof</code> function, for strings in T-SQL?
Looking for something that returns the position of a substring within a string.
in C#

<pre><code class="hljs language-ini">var s = "abcde";
s.IndexOf('c'); // yields 2
</code></pre>

&gt; **Possible Duplicate:**  
&gt; [T-SQL WHERE col IN (&amp;hellip;)](https://stackoverflow.com/questions/1069415/t-sql-where-col-in)  


What is the maximum size for a SQL Server query? (# of characters)

Max size for an IN clause? I think I saw something about Oracle having a 1000 item limit but you could get around this with ANDing 2 INs together. Similar issue in SQL Server?

**UPDATE**
So what would be the best approach if I need to take say 1000 GUIDs from another system (Non Relational Database) and do a &quot;JOIN in code&#39; against the SQL Server? Is it to submit the list of 1000 GUIDs to an IN clause?
Or is there another technique that works more efficiently?

I haven&#39;t tested this but I wonder if I could submit the GUIDs as an XML doc. For example 

    &lt;guids&gt;
        &lt;guid&gt;809674df-1c22-46eb-bf9a-33dc78beb44a&lt;/guid&gt;
        &lt;guid&gt;257f537f-9c6b-4f14-a90c-ee613b4287f3&lt;/guid&gt;
    &lt;/guids&gt;

and then do some kind of XQuery JOIN against the Doc and the Table. Less efficient than 1000 item IN clause?


Maximum size for a SQL Server Query? IN clause? Is there a Better Approach

When you study relational theory foreign keys are, of course, mandatory. But in practice, in every place I worked, table products and joins are always done by specifying the keys explicitly in the query, instead of relying on foreign keys in the DBMS.  

This way, you could of course join two tables by fields that are not meant to be foreign keys, having unexpected results.  

Why do you think that is? Shouldn&#39;t DBMSs enforce that Joins and Products be made only by foreign keys?


EDIT: Thanks for all the answers. It&#39;s clear to me now that the main reason for FKs is reference integrity. But if you design a DB, all relationships in the model (I.E. arrows in the ERD) become Foreign keys, at least in theory, whether or not you define them as such in your DBMS, they&#39;re semantically FKs. I can&#39;t imagine the need to join tables by fields that aren&#39;t FKs. __Can someone give an example that makes sense?__

PS: I&#39;m aware about the fact that N:M relationships become separate tables and not foreign keys, just omitted it for simplicity&#39;s sake.

Why are foreign keys more used in theory than in practice?

I can do SELECT TOP (200) ... but why not BOTTOM (200)?

Well not to get into philosophy what I mean is, how can I do the equivalent of TOP (200) but in reverse (from the bottom, like you&#39;d expect BOTTOM to do...)?

How to select bottom most rows?

I&#39;m looking for a way to update just a portion of a string via MySQL query.  

For example, if I have 10 records all containing &#39;string&#39; as part of the field value (i.e., &#39;something/string&#39;, &#39;something/stringlookhere&#39;, &#39;something/string/etcetera&#39;, is there a way to change &#39;string&#39; to &#39;anothervalue&#39; for each row via one query, so that the result is &#39;something/anothervalue&#39;, &#39;something/anothervaluelookhere&#39;, &#39;something/string/etcetera&#39;, is there a way to change &#39;anothervalue&#39;

MySql - Way to update portion of a string?

in **SQL Server** is possible to execute a SELECT, without reference to a table; something like:

    Select 1.2 +3, &#39;my dummy string&#39;

As **Oracle** does not allow a SELECT without a FROM, I use the dual table for this type of operation; something like:

    Select 1,2+3, &#39;my dummy string&#39; FROM DUAL

There is a better way of doing this type of query? it is good practice to use the dual table?

Select without a FROM clause in Oracle

I&#39;ve got a simple query running against SQL Server 2005

    SELECT * 
    FROM Table 
    WHERE Col = &#39;someval&#39;

The first time I execute the query can take `&gt; 15 secs`. Subsequent executes are back in `&lt; 1 sec`.

How can I get SQL Server 2005 not to use any cached results? I&#39;ve tried running

    DBCC DROPCLEANBUFFERS
    DBCC FREEPROCCACHE

But this seems to have no effect on the query speed (still `&lt; 1 sec`).

How can I clear the SQL Server query cache?

We have a few *huge* databases (20GB+) which mostly contain static lookup data.  Because our application executes joins against tables in these databases, they have to be part of each developers local SQL Server (i.e. they can&#39;t be hosted on a central, shared database server).  

We plan on copying a canonical set of the actual SQL Server database files (*.mdf and *.ldf) and attach them to each developer&#39;s local database.

What&#39;s the best way to find out the local SQL Server instance&#39;s data directory so we can copy the files to the right place?  This will be done via an automated process, so I have to be able to find and use it from a build script.

How do I find the data directory for a SQL Server instance?

Within my rather large database, I would like to find out everywhere a column is referenced within the entire schema (SPs, functions, tables, triggers...).  I don&#39;t want to just do a text search since this will pick up comments and also will find similarly named columns from other tables.  

Does anyone know if/how I can do this?  I use SQL Server 2008.

In SQL Server, how can I find everywhere a column is referenced?

My query is as follows, and contains a subquery within it:

     select count(distinct dNum)
     from myDB.dbo.AQ
     where A_ID in 
      (SELECT DISTINCT TOP (0.1) PERCENT A_ID, 
    			COUNT(DISTINCT dNum) AS ud 
     FROM         myDB.dbo.AQ
     WHERE     M &gt; 1 and B = 0 
     GROUP BY A_ID ORDER BY ud DESC)


The error I am receiving is ...

    Only one expression can be specified in the select list when the subquery is not
    introduced with EXISTS.`

When I run the sub-query alone, it returns just fine, so I am assuming there is some issue with the main query?

Only one expression can be specified in the select list when the subquery is not introduced with EXISTS

    declare @top  int
    set @top = 5
    select top @top * from tablename


Is it possible?

Or any idea for such a logic (i don&#39;t want to use dynamic query)?



Use variable with TOP in select statement in SQL Server without making it dynamic

I am trying to print a selected value, is this possible?

Example:

    PRINT 
        SELECT SUM(Amount) FROM Expense

SQL Server PRINT SELECT (Print a select query result)?

I have two variables, one is called `PaidThisMonth`, and the other is called `OwedPast`. They are both results of some subqueries in SQL. How can I select the smaller of the two and return it as a value titled `PaidForPast`?

The `MIN` function works on columns, not variables.


Getting the minimum of two values in SQL

As PEP8 suggests keeping below the 80 column rule for your python program, how can I abide to that with long strings, i.e.

    s = &quot;this is my really, really, really, really, really, really, really long string that I&#39;d like to shorten.&quot;

How would I go about expanding this to the following line, i.e.

    s = &quot;this is my really, really, really, really, really, really&quot; + 
        &quot;really long string that I&#39;d like to shorten.&quot;

How to write very long string that conforms with PEP8 and prevent E501

I&#39;m pretty new to Python and am completely confused by `.join()` which I have read is the preferred method for concatenating strings.

I tried:

    strid = repr(595)
    print array.array(&#39;c&#39;, random.sample(string.ascii_letters, 20 - len(strid)))
        .tostring().join(strid)

and got something like:

    5wlfgALGbXOahekxSs9wlfgALGbXOahekxSs5

Why does it work like this?  Shouldn&#39;t the `595` just be automatically appended?

What exactly does the .join() method do?

In Perl I can repeat a character multiple times using the syntax:

    $a = &quot;a&quot; x 10; // results in &quot;aaaaaaaaaa&quot;

Is there a simple way to accomplish this in Javascript? I can obviously use a function, but I was wondering if there was any built in approach, or some other clever technique.

Repeat a string in JavaScript a number of times

How do I implement the following (Python pseudocode) in C++?

    if argv[1].startswith(&#39;--foo=&#39;):
        foo_value = int(argv[1][len(&#39;--foo=&#39;):])

(For example, if `argv[1]` is `--foo=98`, then `foo_value` is `98`.)

**Update:** I&#39;m hesitant to look into Boost, since I&#39;m just looking at making a very small change to a simple little command-line tool (I&#39;d rather not have to learn how to link in and use Boost for a minor change).


Content Type	Original Author	Original Content on Stackoverflow
Question	DevelopingChris	View Question on Stackoverflow
Solution 1 - Sql	Scott Ivey	View Answer on Stackoverflow
Solution 2 - Sql	OMG Ponies	View Answer on Stackoverflow
Solution 3 - Sql	richardtallent	View Answer on Stackoverflow
Solution 4 - Sql	Justin Swartsel	View Answer on Stackoverflow

IndexOf function in T-SQL

Sql Problem Overview

Sql Solutions

Solution 1 - Sql

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Solution 3 - Sql

Solution 4 - Sql

How to iterate through a DataTable

How can I find the difference between two angles?

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