`coalesce` is supported in both Oracle and SQL Server and serves essentially the same function as `nvl` and `isnull`. (There are some important differences, `coalesce` can take an arbitrary number of arguments, and returns the first non-null one. The return type for `isnull` matches the type of the first argument, that is not true for `coalesce`, at least on SQL Server.)

Instead of `ISNULL()`, use `NVL()`.

T-SQL:

    SELECT ISNULL(SomeNullableField, &#39;If null, this value&#39;) FROM SomeTable

PL/SQL:

    SELECT NVL(SomeNullableField, &#39;If null, this value&#39;) FROM SomeTable

Also use `NVL2` as below if you want to return other value from the `field_to_check`:

    NVL2( field_to_check, value_if_NOT_null, value_if_null )

Usage: [ORACLE/PLSQL: NVL2 FUNCTION][1]


  [1]: http://www.techonthenet.com/oracle/functions/nvl2.php


You can use the condition `if x is not null then...`. It&#39;s not a function. There&#39;s also the `NVL()` function, a good example of usage here: [NVL function ref][1].


  [1]: http://www.techonthenet.com/oracle/functions/nvl.php

How do you view a stored procedure/function?

Say I have an old function without the original definition - I want to see what it is doing in pg/psql but I can&#39;t seem to figure out a way to do that.

using Postgres version 8.4.1


how to display full stored procedure code?

I am using Windows 7 Enterprise 32 bit. I have used Windows command line, and also used VSTS 2008 command line, but when executing gacutil.exe, there is command not found error.

I am wondering whether I need to install gacutil.exe from somewhere or gacutil.exe is located in somewhere else in my computer (I searched my computer, but find several files called gacutil.exe, I do not know which one should be used)?

BTW: I am using .Net 3.5.

where is gacutil.exe?

In SQL Server we can type `IsNull()` to determine if a field is null.  Is there an equivalent function in PL/SQL?

What is the Oracle equivalent of SQL Server&#39;s IsNull() function?

<p>In SQL Server we can type <code>IsNull()</code> to determine if a field is null.  Is there an equivalent function in PL/SQL?</p>


Is there a way to generate MD5 Hash string of type varchar(32) without using fn_varbintohexstr

    SUBSTRING(master.dbo.fn_varbintohexstr(HashBytes(&#39;MD5&#39;, &#39;email@dot.com&#39;)), 3, 32)

So it could be used inside a view with SCHEMABINDING

Generate MD5 hash string with T-SQL

If I use something like

    [ntext2] &lt;&gt; &#39;1,032.5&#39;,

I get this error:

&gt; The data types ntext and varchar are incompatible in the not equal to operator.

The best possible solution would be if comparison is implemented in the same way for any column type. (&lt;&gt; operator is applicable for both NVARCHAR and INT).


What&#39;s the right way to compare an NTEXT column with a constant value?

Could someone give me some guidance on when I should use `WITH (NOLOCK)` as opposed to `SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED`

What are the pros/cons of each?  Are there any unintended consequences you&#39;ve run into using one as opposed to the other?

WITH (NOLOCK) vs SET TRANSACTION ISOLATION LEVEL READ UNCOMMITTED

As a .NET developer, for what reasons should I prefer SSIS packages over writing code? We have *a ton* of packages in production where I currently work, and they&#39;re a nightmare to both &quot;write&quot; (perhaps draw?) and maintain. Each package looks like a bowl of multicolored spaghetti with C# and VB.NET scripts mixed in at the points where the abstractions break down. To figure out what each &quot;Execute SQL Task&quot; or &quot;Foreach Loop&quot; does, I have to double click the damned thing and browse through a tree of literal values and expressions, scattered across multiple tabs.

I&#39;m open minded, so I&#39;d like to know if any other *good developers* find SSIS more productive than just writing some code. If you do find SSIS more productive, please tell me why.

Should programmers use SSIS, and if so, why?

How can I call stored procedures of sql server with sqlAlchemy?

stored procedures with sqlAlchemy

I want to write reusable code and need to declare some variables at the beginning and reuse them in the script, such as:

    DEFINE stupidvar = &#39;stupidvarcontent&#39;;

    SELECT stupiddata
    FROM stupidtable
    WHERE stupidcolumn = &amp;stupidvar;

How can I declare a variable and reuse it in statements that follow such as in using it SQLDeveloper.

---

**Attempts**

*  Use a DECLARE section and insert the following SELECT statement in `BEGIN` and `END;`. Acces the variable using `&amp;stupidvar`.
*  Use the keyword `DEFINE` and access the variable.
* Using the keyword `VARIABLE` and access the the variable.

But I am getting all kinds of errors during my tries (Unbound variable, Syntax error, Expected `SELECT INTO`...).

How to declare variable and use it in the same Oracle SQL script?

I&#39;ve just made the switch from MS sql server to Oracle.  The query tool I am using is Oracle SQL Developer.  The problem I am having is that I cannot get the query results window to stick around. The query results window being the Grid view for the results.  It seems to show up arbitrarily when I open a new &quot;sql worksheet&quot;.  But not always.  Then once I run a query, it disappears the next time I run one.

Can anyone point me to a consistent way to leave this results grid active? Thanks so much.

Oracle SQL Developer - Query results window with grid missing

I need to write a procedure to normalize a record that have multiple tokens concatenated by one char. I need to obtain these tokens splitting the string and insert each one as a new record in a table. Does Oracle have something like a &quot;split&quot; function?

Is there a function to split a string in PL/SQL?

Is there any Boolean type in Oracle databases, similar to the `BIT` datatype in Ms SQL Server?

Is there any boolean type in Oracle databases?

I&#39;m trying to run a query that has a few columns that are a CLOB datatype. If i run the query like normal, all of those fields just have `(CLOB)` as the value.

I tried using `DBMS_LOB.substr(column`) and i get the error 

    ORA-06502: PL/SQL: numeric or value error: character string buffer too small

How can i query the CLOB column?

How to query a CLOB column in Oracle

Is there a way to get the SQL text for the last few queries?

I am using Microsoft SQL Server 2005

TSQL: Get Last Queries Ran

Can someone explain this two - Index Key Column VS Index Included Column?

Currently, I have an index that has 4 Index Key Column and 0 Included Column.

Thanks



Index Key Column VS Index Included Column

I found [Naming Guidelines][1] from MSDN, but is it any guideline for MSSQL database from Microsoft? 


  [1]: http://msdn.microsoft.com/en-us/library/ms229045.aspx

Database Naming Conventions by Microsoft?

How do I convert a comma separated string to a array?

I have the input &#39;`1,2,3&#39;` , and I need to convert it into an array.


Convert comma separated string to array in PL/SQL

What is the easiest way to INSERT a row if it doesn&#39;t exist, in PL/SQL (oracle)?


I want something like:

    IF NOT EXISTS (SELECT * FROM table WHERE name = &#39;jonny&#39;) THEN
      INSERT INTO table VALUES (&quot;jonny&quot;, null);
    END IF;

But it&#39;s not working.

Note: this table has 2 fields, say, **name** and **age**. But only **name** is PK.

Oracle: how to INSERT if a row doesn&#39;t exist

I wanted to delete some unused schemas on our oracle DB. 

How can I query for all schema names ?

Content Type	Original Author	Original Content on Stackoverflow
Question	Goran	View Question on Stackoverflow
Solution 1 - Sql Server	Shannon Severance	View Answer on Stackoverflow
Solution 2 - Sql Server	BoltClock	View Answer on Stackoverflow
Solution 3 - Sql Server	MinhD	View Answer on Stackoverflow
Solution 4 - Sql Server	FrustratedWithFormsDesigner	View Answer on Stackoverflow

What is the Oracle equivalent of SQL Server's IsNull() function?

Sql Server Problem Overview

Sql Server Solutions

Solution 1 - Sql Server

Solution 2 - Sql Server

Solution 3 - Sql Server

Solution 4 - Sql Server

where is gacutil.exe?

how to display full stored procedure code?

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