QueryNew

Description

Creates an empty query (query object).

Returns

An empty query with a set of named columns, or an empty query.

Category

Query functions

Function syntax

QueryNew(columnlist [, columntypelist[, rowData]])

History

ColdFusion (2018 release) Update 5: You can insert rows in a query object as array of structs. For more information, see Enhancements in QueryNew function.

ColdFusion MX 7: Added  columntypelist  parameter.

ColdFusion 10: Added rowData parameter.

See also

QueryAddColumnQueryAddRowQuerySetCellManaging data types for columns in Query of Queries user guide in the Developing ColdFusion Applications

Parameters

Parameter

Description

columnlist

Comma-delimited list of column names, or an empty string.

columntypelist

(Optional) Comma-delimited list specifying column data types. ColdFusion generates an error if the data you add to the column is not of this type, or if it cannot convert the data to this type. The following data types are valid:

  • Object: Java Object. This is the default column type.
  • Integer: 32-bit integer
  • BigInt: 64-bit integer
  • Double: 64-bit decimal number
  • Decimal: Variable length decimal, as specified by java.math.BigDecimal
  • VarChar: String
  • Binary: Byte array
  • Bit: Boolean (1=True, 0=False)
  • Time: Time
  • Date: Date 
  • Timestamp: Time and date information
 rowData

(Optional) Specifies data to add to the new query. Can be one of:

  • A struct with key/value pairs representing a single row of data, where the key is the column name and the value is the data;
  • an array of structs as per above, for adding multiple rows of data;
  • an array of arrays where each inner array are values for a row of data, in the same order as the columns are specified in the  columntypelist  parameter.

See "Usage" for examples.

Usage

If you specify an empty string in the  columnlist  parameter, use the QueryAddColumn function to add columns to the query .Adobe recommends that you use the optional  columntypelist  parameter. Without this parameter, ColdFusion must try to determine data types when it uses the query object in a query of queries. Determining data types requires additional processing, and can result in errors if ColdFusion does not guess a type correctly .Enhancements in ColdFusion 10 lets you initialize the query data. You can specify a struct, an array of structs, or arrays with single or multiple dimensions to initialize the query as shown in the following example:

myQuery1 = queryNew("id,name","Integer,Varchar", {id=1,name="One"}); 
myQuery2 = queryNew("id,name","Integer,Varchar", 
[ 
{id=1,name="One"}, 
{id=2,name="Two"}, 
{id=3,name="Three"} 
]); 
myQuery3 = queryNew("id,name","Integer,Varchar", [ [1,"One"], [2,"Two"], [3,"Three"] ]);

Example

The following example creates a query object.

<cfscript>
    myQuery = queryNew("id,name,amount","Integer,Varchar,Integer", 
                [ 
                        {id=1,name="One",amount=15}, 
                        {id=2,name="Two",amount=18}, 
                        {id=3,name="Three",amount=32} 
                ]); 
    writeOutput("The new query is:")
    writeDump(myQuery)
</cfscript>

Output

Query object
Query object

Example

The following example uses the QueryNew function to create an empty query with three columns. It populates two rows of the query and displays the contents of the query object and its metadata.

<!--- Create a new three-column query, specifying the column data types ---> 
<cfset myQuery = QueryNew("Name, Time, Advanced", "VarChar, Time, Bit")> 

<!--- Make two rows in the query ---> 
<cfset QueryAddRow(MyQuery, 2)> 

<!--- Set the values of the cells in the query ---> 
<cfset QuerySetCell(myQuery, "Name", "The Wonderful World of CMFL", 1)> 
<cfset QuerySetCell(myQuery, "Time", "9:15 AM", 1)> 
<cfset QuerySetCell(myQuery, "Advanced", False, 1)> 
<cfset QuerySetCell(myQuery, "Name", "CFCs for Enterprise Applications", 2)> 
<cfset QuerySetCell(myQuery, "Time", "12:15 PM", 2)> 
<cfset QuerySetCell(myQuery, "Advanced", True, 2)> 

<h4>The query object contents</h4> 
<cfoutput query = "myQuery"> 
#Name# #Time# #Advanced#<br> 
</cfoutput><br> 
<br> 
<h4>Using individual query data values</h4> 
<cfoutput> 
#MyQuery.name[2]# is at #MyQuery.Time[2]#<br> 
</cfoutput><br> 
<br> 
<h4>The query metadata</h4> 
<cfset querymetadata=getMetaData(myQuery)> 
<cfdump var="#querymetadata#">

Enhancements in QueryNew function

In ColdFusion (2018 release) Update 5, there is an enhancement in the function QueryNew, related to how a query object is populated.

In previous versions of ColdFusion, while defining the parameters in the QueryNew function, you had to first define the columns of the query object, the data types of the columns, and finally, the row data.

For example,

<cfscript>
 q=queryNew("foo,bar", "", [{foo="foo"},{bar="bar"},{foo="foo1",bar="bar1"}])
 writedump(q)
</cfscript>

In this update, you can insert rows in a query object as array of structs. The query object interprets the struct keys as column names and assumes the appropriate data type.

For example,

<cfscript> 
 myquery=QueryNew([ 
  {"Id":101,"Name":"John Adams","Paid":FALSE}, 
  {"Id":102,"Name":"Samuel Jackson","Paid":TRUE}, 
  {"Id":103,"Name":"Gal Gadot","Paid":TRUE}, 
  {"Id":104,"Name":"Margot Robbie","Paid":FALSE} 
 ]) 
 writedump(myquery) 
</cfscript>

In the snippet above, you can see that the struct keys Id, Name, and Paid are the columns of the query object and the values are the row values of the query object.

You can also create the query object by using named parameters.

For examples,

Use the parameter data to populate the query object with values as array of structs.

<cfscript>
 mydata = queryNew(data=[
     {"id":1,"title":"Hello World"}, 
     {"id":2,"title":"How are you"}
    ]);
 writeDump(mydata);
</cfscript>

Use the parameter columnNames to create the columns for the query object.

<cfscript>
 data = queryNew(columnNames="Year,Salary")
 writeDump(data);
</cfscript>

 Adobe

Kapjon segítséget gyorsabban és könnyebben!

Új felhasználó?