MACROMEDIA COLDFUSION MX 61-DEVELOPING COLDFUSION MX, Develop Manual

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Query of Queries user guide 473
Using Queries of Queries with numeric dates
If you create a query object with
QueryNew()
and populate a column with dates in numeric
format (for example, 12/24/02), the dates are preserved as a string inside the query object until a
Query of Queries is applied to the query object. When ColdFusion applies a Query of Queries to
the query object, it converts the string representations into date objects. If you want to convert
the data to its original format, use the
DateFormat
function and apply the "mm/dd/yy" mask.
The following code demonstrates this:
<cfset q1=queryNew("col1, col2")>
<cfset queryAddRow(q1,2)>
<cfset q1['col1'][1] = 1>
<cfset q1['col2'][1] = "12/24/2002">
<cfset q1['col1'][2] = 2>
<cfset q1['col2'][2] = "3/26/04">
Query object date before q of q<br>
<cfoutput>#q1['col2'][1]#</cfoutput><br><br>
<cfquery name="qoq" dbtype="query">
select * from q1
</cfquery>
Query object date after q of q<br>
<cfoutput>#q1['col2'][1]#</cfoutput><br><br>
Now reformat it:
<cfoutput>#dateFormat(q1['col2'][1], "mm/dd/yy")#</cfoutput>
Understanding Query of Queries performance
Query of Queries performs very well on single-table query objects that were accessed directly
from a database. This is because ColdFusion MX stores meta information for a query object
accessed from a database. It does not perform as well on large query objects derived from a
QueryNew()
function, because ColdFusion MX must derive the metadata at runtime.
PRIOR PRIVILEGES PROCEDURE PUBLIC READ
REAL REFERENCES RELATIVE RESTRICT REVOKE
RIGHT ROLLBACK ROWS SCHEMA SCROLL
SECOND SECTION SELECT SESSION SESSION_USER
SET SIZE SMALLINT SOME SPACE
SQL SQLCODE SQLERROR SQLSTATE SUBSTRING
SUM SYSTEM_USER TABLE TEMPORARY THEN
TIME TIMESTAMP TIMEZONE_HOUR TIMEZONE_MINUTE TO
TRAILING TRANSACTION TRANSLATE TRANSLATION TRIM
TRUE UNION UNIQUE UNKNOWN UPDATE
UPPER USAGE USER USING VALUE
VALUES VARCHAR VARYING VIEW WHEN
WHENEVER WHERE WITH WORK WRITE
YEAR ZONE