Num_children() function

num_children() — Counts the number of child nodes of a parent node.

Syntax

The num_children() function returns a tree and takes a tree parameter:

tree num_children(tree input)

Return value

The num_children() function returns a tree.

Description

The num_children() function finds the number of child nodes of a parent node. The num_children() function takes 1 parameter.

Examples

You can try the following examples against your own data in the GoToAssist search field, or against fictitious data in the Query Sandbox:

• Example 1: Count interface children
• Example 2: Count children of Directory item properties
• Example 3: Count children of systems with low disk space

Example 1: Count interface children

Query: How many children does each interface have?

SELECT num_children(interface) 
FROM /network/device

Results: Depending on the database, this query returns results similar to this:

row
   num_children(interface)5
row
   num_children(interface)26
row
   num_children(interface)2
row
   num_children(interface)174 
   . . .

Example 2: Count children of Directory item properties

Query: How many children do the Directory Items properties have?

SELECT properties/name, num_children(properties)
FROM /directory/item

Results: Depending on the database, this query returns results similar to this:

row
   /properties/name VOLANS
   num_children(properties) 20
row
   /properties/name EARTH
   num_children(properties) 15
row
   /properties/name JUPITER
   num_children(properties) 16
row
   /properties/name GRUS
   num_children(properties) 21 
   . . .

Example 3: Children of systems with low disk space

Query: How many child nodes do the systems with low disk space have?

SELECT num_children(systemname) 
FROM %free disk space% 
WHERE freespace < 1000000000
AND description = 'Local Fixed Disk'

Results: Depending on the database, this query returns results similar to this:

SELECT num_children(systemname) 
FROM %free disk space% 
WHERE freespace < 1000000000
AND description = 'Local Fixed Disk'

Results: Depending on the database, this query returns results similar to this:

row
   has_history(systemname) 0
row
   has_history(systemname) 0
row
   has_history(systemname) 0

To see other PQL functions, see Functions.

Related topics

• Functions
• Operators
• Expressions
• Read about PQL

| Views: 1025 | Last Updated: Thu, May 09 2013 2:28 PM

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