Incorrect result while using DBT macro

Question

Running a macro using dbt and getting incorrect results.

I am running the below macro:

{% set value = 0 %}
 {% for key , v in metrics.items() %}
     {% if col in v %}
          {% set value = value + 1 %}
          {{value}} 
           {{key}}({%- if relation_alias %}{{ relation_alias }}.{{ col|trim }}){%- endi -%}           
           {% endif %}           
 {% endfor %}          
 {{ value }}

I am getting the value as 0 outside the for loop even after the if condition is met. I am expecting value as 1 after for loop is executed. Kindly suggest.

Answer 1

You need to put your variable into a namespace in order for it to be updated in the loop:

{% set ns = namespace(value = 0) %}
{% for key , v in metrics.items() %}
    {% if col in v %}
        {% set ns.value = ns.value + 1 %}
        {{value}} 
        {{key}}({%- if relation_alias %}{{ relation_alias }}.{{ col|trim }}){%- endif -%}           
    {% endif %}           
 {% endfor %}          
 {{ ns.value }}