Query of Queries is based on manipulating the recordset, which you can create using the cfquery tag and other ways.
When you execute a database query, Adobe ColdFusion retrieves the data in a recordset. In addition to presenting recordset data to the user, you can manipulate this recordset to improve the performance of your application.
Because a recordset contains rows (records) and columns (fields), you can think of it as a virtual database table, or as a spreadsheet. For example, the cfpop tag retrieves a recordset in which each row is a message and each column is a message component, such as To, From, and Subject.

Creating a recordset

You can perform a Query of Queries on any ColdFusion tag or function that generates a recordset, including the following:

Creating a recordset with the QueryNew() function

In addition to creating a recordset by using a cfquery or other CFML tags, you can create it with the QueryNew function.

  1. Create a ColdFusion page with the following content:

    <html>
    <head>
    <title>The queryNew function</title>
    </head>
    <body>
    <h2>QueryNew Example</h2>

    <!--- Create a query, specify data types for each column. --->
    <cfset qInstruments = queryNew("name, instrument, years_playing",
    "CF_SQL_VARCHAR, CF_SQL_VARCHAR, CF_SQL_INTEGER")>

    <!--- Add rows. --->
    <cfset newrow = queryaddrow(qInstruments, 3)>

    <!--- Set values in cells. --->
    <cfset temp = querysetcell(qInstruments, "name", "Thor", 1)>
    <cfset temp = querysetcell(qInstruments, "instrument", "hammer", 1)>
    <cfset temp = querysetcell(qInstruments, "years_playing", "1000", 1)>

    <cfset temp = querysetcell(qInstruments, "name", "Bjorn", 2)>
    <cfset temp = querysetcell(qInstruments, "instrument", "sitar", 2)>
    <cfset temp = querysetcell(qInstruments, "years_playing", "24", 2)>

    <cfset temp = querysetcell(qInstruments, "name", "Raoul", 3)>
    <cfset temp = querysetcell(qInstruments, "instrument", "flute", 3)>
    <cfset temp = querysetcell(qInstruments, "years_playing", "12", 3)>

    <!--- Output the query. --->
    <cfoutput query="qInstruments">
    <pre>#name# #instrument# #years_playing#</pre>
    </cfoutput>

    <h3>Individual record retrieval:</h3>
    <cfoutput>
    <p>#qInstruments.name[2]# has played #qInstruments.instrument[2]# for
    #qInstruments.years_playing[2]# years.</p>
    </cfoutput>

    </body>
    </html>

  2. Save the page as queryNew.cfm in the myapps directory under the web_root directory.
  3. Display queryNew.cfm in your browser

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