Difference between Event and Trace Log

Event log: 

It records diagnostic information generated by Microsoft Business Connectivity Services. It also records error messages.

Trace log: 

It also records diagnostic information generated by Microsoft Business Connectivity Services. It contains more in-depth information, such as stack traces and informational messages. The trace log gives more-in-depth information than the event Log.

Reference: Search 2010 Architecture and Scale - Part 1 Crawl

Difference between crawl database and crawl component

What is a crawl database?

In Search Server 2010, a crawl database contains data that are interrelated with the location of content sources, crawl schedules, and other information specific to crawl operations for a specific Search service application. The database load can be distributed by adding crawl databases to different computers that are running SQL Server. Crawl databases are associated with crawl components and can be associated with specific hosts by creating host distribution rules.

What is a crawl component?

In Search Server 2010, a crawl component is used to process crawls of content sources and propagates the resulting index files to query components. It adds information about the location and crawl schedule of content sources to their associated crawl databases. Crawl components are associated with a single Search service application and can be added to different farm servers for distributing the crawl Load.

Reference: Search 2010 Architecture and Scale - Part 1 Crawl

how to apply custom master page to application pages

I came across a position, where i have an application page developed for user requirement and the user desires the look and feel of this page to me similar to other pages in the context.

I tried so many alternatives but didn’t get prospered; I found the right to use the default.master or custom master page for application pages.

First thing is that if you need to use a masterpage from the site context, you want to have the similar content placeholders as are expected by the master page.

Master pages can be loaded dynamically. This can be done by assigning a master page file to the MasterPageFile property in the Page object. This property may only be assigned in the Page PreInit event, this is the first event executed page execution lifecycle.

Copy and paste this below code in your custom application page and deploy the assembly to GAC and see, it should work now.

protected override void OnPreInit(EventArgs e)
{
base.OnPreInit(e);
SPWeb TestWeb = SPControl.GetContextSite(Context).OpenWeb();
string strUrl = TestWeb.ServerRelativeUrl + “/_catalogs/masterpage/Test.master”;
this.MasterPageFile = strUrl;
}

Where “Test.master” has to be stored in master page gallery of the site.

Probably you may get a memory leak for SPWeb object , so you can use this simple code instead of the above

protected override void OnPreInit(EventArgs e)
{
base.OnPreInit(e);
this.MasterPageFile = SPContext.Current.Web.MasterUrl;
}