[LON-CAPA-cvs] cvs: loncom /html/adm/help/tex Domain_Configuration_Course_Defaults.tex

[raeburn]

raeburn		Mon Sep 19 13:12:18 2016 EDT

  Modified files:              
    /loncom/html/adm/help/tex	Domain_Configuration_Course_Defaults.tex 
  Log:
  - Set default lifetimes for temporary MySQL tables containing student
    performance data for each course (homeserver only), by course type. 
  
  
Index: loncom/html/adm/help/tex/Domain_Configuration_Course_Defaults.tex
diff -u loncom/html/adm/help/tex/Domain_Configuration_Course_Defaults.tex:1.6 loncom/html/adm/help/tex/Domain_Configuration_Course_Defaults.tex:1.7
--- loncom/html/adm/help/tex/Domain_Configuration_Course_Defaults.tex:1.6	Sat May 30 21:47:32 2015
+++ loncom/html/adm/help/tex/Domain_Configuration_Course_Defaults.tex	Mon Sep 19 13:12:18 2016
@@ -34,7 +34,7 @@
 \item \textbf{Defaults that can be overridden in an individual course by a Domain
 Coordinator}
 
-Currently, there are four domain defaults of this type (which can be overridden
+Currently, there are five domain defaults of this type (which can be overridden
 via the ``View or modify a course or community'' interface). 
 
 \begin{itemize}
@@ -50,6 +50,21 @@
 answer submission.  After processing a student's answer a new page is displayed. The setting 
 to disable a  button, (with or without a timeout), applies to the button in the old page in
 the time period before the new page is loaded by the browser.
+
+\item lifetime of temporary tables (course's homeserver)
+
+The default lifetime (since last update) for ``temporary'' MySQL tables 
+containing student performance data is 172800s (i.e., 2 days). A different default
+lifetime can be set by course type, which will apply to MySQL tables on the course's 
+homeserver only.
+
+A reason to do this might be where a domain has created a custom script to export
+a course's grade data, by running SQL queries against the temporary tables.
+
+Note: student performance data are stored permanently in GDBM files; the temporary MySQL
+tables are simply used to speed up display when a Course Coordinator uses the 
+Assessment Chart or Statistics functions in a course.
+
 \end{itemize}
 
 \end{itemize}