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Displaying keyword search results 1 - 8
Created by Dr. Xi on March 07, 2011 16:23:40    Last update: March 07, 2011 16:25:05
Oracle operator || doesn't work for MySQL. Looks like I have to use the concat function: mysql> select 'abc' || '123'; +----------------...
Created by Fang on August 23, 2010 22:55:58    Last update: August 24, 2010 15:45:04
The tags XML flow control tags are exactly the same as their Core flow control equivalents, except that the test condition with a boolean EL expression is replaced by the select condition with an XPath expression. In the case of the forEach tag, the items attribute is replaced with the select attribute. In a test condition, the XPath expression is evaluated to a boolean value by the rules of the XPath boolean() function, which converts its argument to a boolean as follows: a number is true if and only if it is neither positive or negative zero nor NaN. a node-set is true if and only if it is non-empty. a string is true if and only if its length is non-zero. an object of...
Created by Fang on August 18, 2010 20:07:46    Last update: August 18, 2010 20:11:36
JSTL uses XPath expressions as a concise notation to specify or select parts of an XML document. JSTL provides EL like expressions to access web application data and comes with the core function library of the XPath specification. Accessing Web Application Data XPath Expression Mapping $foo pageContext.findAttribute("foo") $param:foo request.getParameter("foo") $header:foo request.getHeader("foo") $cookie:foo maps to the cookie's value for name foo $initParam:foo application.getInitParameter("foo") $pageScope:foo pageContext.getAttribute("foo", PageContext.PAGE_SCOPE) $requestScope:foo pageContext.getAttribute("foo", PageContext.REQUEST_SCOPE) $sessionScope:foo pageContext.getAttribute("foo", PageContext.SESSION_SCOPE) $applicationScope:foo pageContext.getAttribute("foo", PageContext.APPLICATION_SCOPE) For example, to find the bar element whose x attribute equals the value of the HTTP request parameter named paramName : /foo/bar[@x=$param:paramName] Java Type to XPath Type Mappings XPath Type Java Type java.lang.Boolean boolean java.lang.Number number java.lang.String string Object exported by <x:parse> node-set Please note that JSTL, as of version 1.2,...
Created by Dr. Xi on March 23, 2009 23:02:57    Last update: March 23, 2009 23:07:28
Oracle function instr searches the occurrence of a sub-string in a string. It returns the index of the first match. It is similar to the Java String.indexOf function, with the exception that the index is 1 based, not 0 based. -- search for OR from the beginning, returns 2 ...
Created by Dr. Xi on September 29, 2008 23:05:12    Last update: September 29, 2008 23:06:16
These variables are set or used by the Unix shell to modify its behavior. Variable Description ENV=file Name of script that gets executed at startup; Usually, ENV=$HOME/.kshrc FCEDIT=file Editor used by fc (fix command) command. If $FCEDIT is not defined, use $EDITOR, otherwise use the default (vi or ed). FPATH=dirs Directories to search for function definitions; undefined functions are set via typeset -fu . FPATH is searched when these functions are first referenced. HISTFILE=file File in which to store command history. Default is $HOME/.sh_history for Korn shell, $HOME/.bash_history for Bash. If not set, history is lost after logout. HISTSIZE=n Max number of commands to keep in history. HOME=dir Home directory; set by login from passwd file. IFS='chars' Internal field separators. Default is space, tab, and...
Created by Dr. Xi on September 21, 2008 21:04:24    Last update: September 21, 2008 22:27:36
IE uses Notepad as the default editor when you select "View Source" from a web page. You can change it to your favorite editor by adding a couple of keys to the registry: Start regedit Navigate to HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Internet Explorer\ Add key View Source Editor Under View Source Editor , add key Editor Name Change the default string value to the full path of your favorite editor. The following is the registry entry for vim (full tip for vim is available from the vim wiki ): Windows Registry Editor Version 5.00 [HKEY_... It is probably easier (less error prone) to edit this in a file and import it back into the registry. The contents of gvim.vbs are: '--- gVim.vbs ------------------------------------... It is OK to use gvim.exe...
Created by Dr. Xi on September 13, 2008 20:52:47    Last update: September 15, 2008 23:04:35
The text source of the stored objects (including stored procedures) are made available in Oracle by three views: USER_SOURCE describes the text source of the stored objects owned by the current user. This view does not display the OWNER column. ALL_SOURCE describes the text source of the stored objects accessible to the current user. DBA_SOURCE describes the text source of all stored objects in the database. These are the columns: Column Name Description OWNER Owner of the object NAME Name of the object TYPE Type of object: FUNCTION, JAVA SOURCE, PACKAGE, PACKAGE BODY, PROCEDURE, TRIGGER, TYPE, TYPE BODY LINE Line number of this line of source TEXT Text source of the stored object If you want to search for a certain keyword in the source,...
Created by Dr. Xi on August 11, 2007 23:19:26    Last update: August 12, 2007 01:39:33
For SQL Server 2000 and above, there are three functions: SELECT @@IDENTITY When a record is inserted into a table with a identity column, the function @@IDENTITY returns the last identity value that was inserted in the database on the same open connection. If a trigger adds a record into another table, which happens to have an identity column, @@IDENTITY will now return this value instead. SELECT IDENT_CURRENT('tablename') This will give you the most recent identity value for the given table regardless of who inserted it. SELECT SCOPE_IDENTITY() SCOPE_IDENTITY shows the most recently inserted IDENTITY in the current scope (which ignores any triggers that might fire). For SQL Server version prior to 2000, it is customary to use a stored procedure: CREATE PROCEDURE myProc @param1 INT AS......