MACROMEDIA COLFUSION MX 7-CFML, Справочник

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QueryAddColumn 795
Usage
You can add columns to query objects, such as queries retrieved with the
cfquery
tag or queries
created with the
QueryNew
function. You cannot use the
QueryAddColumn
function on a cached
query. This function is useful for generating a query object from the arrays of output parameters
that Oracle stored procedures can generate.
Macromedia recommends that you use the optional
datatype
parameter. Without this
parameter, ColdFusion must try to determine the column’s data type when it uses the query
object in a query of queries. Determining the data type requires additional processing, and can
result in errors if ColdFusion does not guess the type correctly.
Example
The following example creates a new query object, uses the
QueryAddColumn
function to add
three columns to the object, and displays the results. Because two of the arrays that provide the
data are shorter than the third, QueryAddColumn adds padding to the corresponding columns in
the query.
<!--- Make a query. --->
<cfset myQuery = QueryNew("")>
<!--- Create an array. --->
<cfset FastFoodArray = ArrayNew(1)>
<cfset FastFoodArray[1] = "French Fries">
<cfset FastFoodArray[2] = "Hot Dogs">
<cfset FastFoodArray[3] = "Fried Clams">
<cfset FastFoodArray[4] = "Thick Shakes">
<!--- Use the array to add a column to the query. --->
<cfset nColumnNumber =
QueryAddColumn(myQuery, "FastFood", "VarChar",
FastFoodArray)>
<!--- Create a second array. --->
<cfset FineCuisineArray = ArrayNew(1)>
<cfset FineCuisineArray[1] = "Lobster">
<cfset FineCuisineArray[2] = "Flambe">
<!--- Use the array to add a second column to the query. --->
<cfset nColumnNumber2 =
QueryAddColumn(myQuery, "FineCuisine", "VarChar",
FineCuisineArray)>
<!--- Create a third array. --->
<cfset HealthFoodArray = ArrayNew(1)>
<cfset HealthFoodArray[1] = "Bean Curd">
<cfset HealthFoodArray[2] = "Yogurt">
<cfset HealthFoodArray[3] = "Tofu">
<!--- Use the array to add a third column to the query. --->
<cfset nColumnNumber3 =
QueryAddColumn(myQuery, "HealthFood", "VarChar",
HealthFoodArray)>
<!--- Display the results. --->
<table cellspacing = "2" cellpadding = "2" border = "0">
<tr>
<th align = "left">Fast Food</th>
<th align = "left">Fine Cuisine</th>