the `&amp;` is the default value for `DEFINE`, which allows you to use substitution variables.  I like to turn it off using

    SET DEFINE OFF

then you won&#39;t have to worry about escaping or CHR(38).  

`|| chr(38) ||`

This solution is perfect.

Set the define character to something other than &amp;

&lt;pre&gt;
SET DEFINE ~
create table blah (x varchar(20));
insert into blah (x) values (&#39;blah&amp;amp;amp&#39;);
select * from blah;

X                    
-------------------- 
blah&amp;amp;amp 

&lt;/pre&gt;

    insert into AGREGADORES_AGREGADORES (IDAGREGADOR,NOMBRE,URL)
    values (2,&#39;Netvibes&#39;,
    &#39;http://www.netvibes.com/subscribe.php?type=rss&#39; || chr(38) || &#39;amp;url=&#39;);

    SELECT &#39;Free &amp;&#39; || &#39; Clear&#39; FROM DUAL;

`select &#39;one&#39;||&#39;&amp;&#39;||&#39;two&#39; from dual`

The real answer is you need to set the escape character to &#39;\&#39;:
SET ESCAPE ON

The problem may have occurred either because escaping was disabled, or the escape character was set to something other than &#39;\&#39;.  The above statement will enable escaping *and* set it to &#39;\&#39;.

----------

None of the other answers previously posted actually answer the original question.  They all work around the problem but don&#39;t resolve it.


add this before your request

    set define off;

Is it possible to create an instance of a class by name? Something like:

    NSString* className = @&quot;Car&quot;;
    id* p = [Magic createClassByName:className];
    [p turnOnEngine];

I don&#39;t know if this is possible in objective-c but seems like it would be,


Create objective-c class instance by name?

To put it simply, I&#39;m trying to get scrolling in emacs like in vim and most other editors; when I&#39;m for example, two lines from the bottom/top, and I press down/up (&lt;kbd&gt;Ctrl&lt;/kbd&gt;-&lt;kbd&gt;p&lt;/kbd&gt;,&lt;kbd&gt;n&lt;/kbd&gt;, &lt;kbd&gt;↑&lt;/kbd&gt;,&lt;kbd&gt;↓&lt;/kbd&gt;) it goes only one line up or down, not half the screen.


How to scroll line by line in GNU Emacs?

While attempting to execute SQL insert statements using [Oracle SQL Developer][1] I keep generating an &quot;Enter substitution value&quot; prompt:

    insert into agregadores_agregadores 
    (
     idagregador,
     nombre,
     url
    ) 
    values 
    (
     2,
     &#39;Netvibes&#39;,
     &#39;http://www.netvibes.com/subscribe.php?type=rss\&amp;amp;url=&#39;
    );
I&#39;ve tried [escaping the special character in the query][2] using the &#39;\&#39; above but I still can&#39;t avoid the ampersand, &#39;&amp;&#39;, causing a string substitution.


  [1]: http://www.oracle.com/technology/products/database/sql_developer/index.html
  [2]: http://download.oracle.com/docs/cd/B10501_01/text.920/a96518/cqspcl.htm

Oracle SQL escape character (for a &#39;&amp;&#39;)

While attempting to execute SQL insert statements using <a href="http://www.oracle.com/technology/products/database/sql_developer/index.html" target="_blank" rel="noopener noreferrer">Oracle SQL Developer</a> I keep generating an "Enter substitution value" prompt:
<pre><code class="hljs language-sql">insert into agregadores_agregadores 
(
 idagregador,
 nombre,
 url
) 
values 
(
 2,
 'Netvibes',
 'http://www.netvibes.com/subscribe.php?type=rss\&#x26;amp;url='
);
</code></pre>
I've tried <a href="http://download.oracle.com/docs/cd/B10501_01/text.920/a96518/cqspcl.htm" target="_blank" rel="noopener noreferrer">escaping the special character in the query</a> using the '' above but I still can't avoid the ampersand, '&#x26;', causing a string substitution.

I have a transaction that contains multiple SQL Statements (INSERT, UPDATE and/or DELETES). When executing, I want to ignore Duplicate Error statements and continue onto the next statement. What&#39;s the best way of doing that?


How to Ignore &quot;Duplicate Key&quot; error in T-SQL (SQL Server)

What is the main purpose of using [CROSS APPLY][1]?

I have read (vaguely, through posts on the Internet) that `cross apply` can be more efficient when selecting over large data sets if you are partitioning. (Paging comes to mind)

I also know that `CROSS APPLY` doesn&#39;t require a UDF as the right-table.

In most `INNER JOIN` queries (one-to-many relationships), I could rewrite them to use `CROSS APPLY`, but they always give me equivalent execution plans. 

Can anyone give me a good example of when `CROSS APPLY` makes a difference in those cases where `INNER JOIN` will work as well?


---

**Edit:**

Here&#39;s a trivial example, where the execution plans are exactly the same.  (Show me one where they differ and where `cross apply` is faster/more efficient)

    create table Company (
    	companyId int identity(1,1)
    ,	companyName varchar(100)
    ,	zipcode varchar(10) 
    ,	constraint PK_Company primary key (companyId)
    )
    GO
    
    create table Person (
    	personId int identity(1,1)
    ,	personName varchar(100)
    ,	companyId int
    ,	constraint FK_Person_CompanyId foreign key (companyId) references dbo.Company(companyId)
    ,	constraint PK_Person primary key (personId)
    )
    GO
    
    insert Company
    select &#39;ABC Company&#39;, &#39;19808&#39; union
    select &#39;XYZ Company&#39;, &#39;08534&#39; union
    select &#39;123 Company&#39;, &#39;10016&#39;
    
    
    insert Person
    select &#39;Alan&#39;, 1 union
    select &#39;Bobby&#39;, 1 union
    select &#39;Chris&#39;, 1 union
    select &#39;Xavier&#39;, 2 union
    select &#39;Yoshi&#39;, 2 union
    select &#39;Zambrano&#39;, 2 union
    select &#39;Player 1&#39;, 3 union
    select &#39;Player 2&#39;, 3 union
    select &#39;Player 3&#39;, 3 
    
    
    /* using CROSS APPLY */
    select *
    from Person p
    cross apply (
    	select *
    	from Company c
    	where p.companyid = c.companyId
    ) Czip
    
    /* the equivalent query using INNER JOIN */
    select *
    from Person p
    inner join Company c on p.companyid = c.companyId


  [1]: http://technet.microsoft.com/en-us/library/ms175156.aspx

When should I use CROSS APPLY over INNER JOIN?

I&#39;m trying to get the ip, user, and most recent timestamp from a table which may contain both the current ip for a user and one or more prior ips. I&#39;d like one row for each user containing the most recent ip and the associated timestamp. So if a table looks like this:


    username      |  ip      |  time_stamp  
    --------------|----------|--------------  
    ted           | 1.2.3.4  | 10  
    jerry         | 5.6.6.7  | 12  
    ted           | 8.8.8.8  | 30  



I&#39;d expect the output of the query to be:

    jerry    |  5.6.6.7   |  12
    ted      |  8.8.8.8   |  30  

Can I do this in a single sql query? In case it matters, the DBMS is Postgresql.

SQL query to get most recent row for each instance of a given key

In [Oracle SQL Developer][1], if I&#39;m viewing the information on a table, I can view the constraints, which let me see the foreign keys (and thus which tables are referenced by this table), and I can view the dependencies to see what packages and such reference the table. But I&#39;m not sure how to find which tables reference the table.

For example, say I&#39;m looking at the `emp` table. There is another table `emp_dept` which captures which employees work in which departments, which references the `emp` table through `emp_id`, the primary key of the `emp` table. Is there a way (through some UI element in the program, not through SQL) to find that the `emp_dept` table references the `emp` table, without me having to know that the `emp_dept` table exists?


  [1]: http://www.oracle.com/technology/products/database/sql_developer/index.html

How can I find which tables reference a given table in Oracle SQL Developer?

How can I select data in the same query from two different databases that are on two different servers in SQL Server?

Selecting data from two different servers in SQL Server

I have a Rails application that I&#39;m running on my server. When I go to a remote desktop and attempt to load the application, the server takes a good 3-4 minutes to respond with a simple HTML page. However, when I load up the page locally on the server, the page shows up in just a second. I tried pinging the server from my remote desktop and the pings are going through successful in a reasonable amount of time. 

This all seems to have started after I installed Oracle&#39;s basic client and SQLPLUS. Should I suspect Oracle? Has anyone experienced anything similar to this?

Webrick is very slow to respond. How to speed it up?

Probably a classic... Would you know a easy trick to retrieve an UTC value of SYSDATE on Oracle (best would be getting something working on the 8th version as well).

For now I&#39;ve custom function :(

Cheers,

Stefan

How to get UTC value for SYSDATE on Oracle

In TSQL I could use something like `Select [table] from tablename` to select a column named &quot;table&quot;.

How do I do this for reserved words in oracle? 

Edit: I&#39;ve tried square braces, double quotes, single quotes, and backquotes, they don&#39;t work...

As a further clarification, I have a column which someone named comment.  As this is a reserved word oracle is chucking a wobbly trying to select with it, its failing when parsing the query.  I&#39;ve tried Select &quot;comment&quot; from tablename but it didn&#39;t work.  I&#39;ll check case and come back.

How do I escape a reserved word in Oracle?

What is the difference between varchar and varchar2?

What is the difference between varchar and varchar2 in Oracle?

I want to output some braces in a java MessageFormat. For example I know the following does not work:

    MessageFormat.format(&quot;  public {0} get{1}() {return {2};}\n\n&quot;, type, upperCamel, lowerCamel);

Is there a way of escaping the braces surrounding &quot;return {2}&quot;?

Can I escape braces in a java MessageFormat?

I’m using JavaScript to pull a value out from a hidden field and display it in a textbox. The value in the hidden field is encoded.

For example,

&lt;!-- language: lang-html --&gt;

    &lt;input id=&#39;hiddenId&#39; type=&#39;hidden&#39; value=&#39;chalk &amp;amp; cheese&#39; /&gt;

gets pulled into

&lt;!-- language: lang-html --&gt;

    &lt;input type=&#39;text&#39; value=&#39;chalk &amp;amp; cheese&#39; /&gt;

via some jQuery to get the value from the hidden field (it’s at this point that I lose the encoding):

&lt;!-- language: lang-js --&gt;

    $(&#39;#hiddenId&#39;).attr(&#39;value&#39;)

The problem is that when I read `chalk &amp;amp; cheese` from the hidden field, JavaScript seems to lose the encoding. I do not want the value to be `chalk &amp; cheese`. I want the literal `amp;` to be retained.

Is there a JavaScript library or a jQuery method that will HTML-encode a string?

HTML-encoding lost when attribute read from input field

Is there an escape character for a double quote in xml?  I want to write a tag like:

    &lt;parameter name=&quot;Quote = &quot; &quot;&gt;

but if I put &quot;, then that means string has ended.  I need something like this (c++):

    printf(&quot;Quote = \&quot; &quot;);

Is there a character to write before the double quote to escape it?

Escape double quote character in XML

Are there any classes/functions available to be used for easy JSON escaping? I&#39;d rather not have to write my own.

How to escape JSON string?

Is there a recommended way to escape `&lt;`, `&gt;`, `&quot;` and `&amp;` characters when outputting HTML in plain Java code?  (Other than manually doing the following, that is).

    String source = &quot;The less than sign (&lt;) and ampersand (&amp;) must be escaped before using them in HTML&quot;;
    String escaped = source.replace(&quot;&lt;&quot;, &quot;&amp;lt;&quot;).replace(&quot;&amp;&quot;, &quot;&amp;amp;&quot;); // ...



What is the recommended way to escape HTML symbols in plain Java?

In **Oracle SQL Developer**, one can list the data in a table using the Data tab when viewing a table. there where can add, delete, edit or just viewing records of table currently viewd

the problem is that we often really need to view more than one table at once, then we need more than one tab opened, thing that i dont know how to do that, any sugestion. tq in advance

Oracle SQL Developer multiple table views

I am evaluating [Oracle SQL Developer][1].

My `tnsnames.ora` is populated, and a `tnsping` to a connection defined in `tnsnames.ora` works fine. Still, SQL Developer does not display any connections.

[Oracle SQL Developer Soars ][2] mentions, that if
&gt; you have Oracle client software and a tnsnames.ora file already installed on your machine, Oracle SQL Developer will automatically populate the Connections navigator from the net service names defined in tnsnames.ora.

I also tried to set my `TNS_ADMIN` environment variable, but after restarting SQL Developer there are still no connections displayed.

Any ideas?&lt;br&gt;
Anyone successfully working with SQL Developer and tnsnames.ora?

  [1]: http://www.oracle.com/technology/products/database/sql_developer/index.html
  [2]: http://www.oracle.com/technology/oramag/oracle/06-may/o36sql.html

Use tnsnames.ora in Oracle SQL Developer

When I try to execute this statement in Oracle SQL Developer 2.1 a dialog box *&quot;Enter Substitution Variable&quot;* pops up asking for a replacement value for *TOBAGO*,

    update t set country = &#39;Trinidad and Tobago&#39; where country = &#39;trinidad &amp; tobago&#39;;

How can I avoid this without resorting to `chr(38)` or `u&#39;trinidad \0026 tobago&#39;` which both obscure the purpose of the statement?

How to avoid variable substitution in Oracle SQL Developer

How to export Oracle DB data using SQL Developer? I need all data, tables, constraints, structure and so on.

Content Type	Original Author	Original Content on Stackoverflow
Question	ian_scho	View Question on Stackoverflow
Solution 1 - Sql	Neil Kodner	View Answer on Stackoverflow
Solution 2 - Sql	Aseem	View Answer on Stackoverflow
Solution 3 - Sql	RC.	View Answer on Stackoverflow
Solution 4 - Sql	Jeffrey Kemp	View Answer on Stackoverflow
Solution 5 - Sql	drj	View Answer on Stackoverflow
Solution 6 - Sql	Izo	View Answer on Stackoverflow
Solution 7 - Sql	Terrible Tadpole	View Answer on Stackoverflow
Solution 8 - Sql	Helali	View Answer on Stackoverflow

Oracle SQL escape character (for a '&')

Sql Problem Overview

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How to scroll line by line in GNU Emacs?

Create objective-c class instance by name?

Attributions