Problems writing conditional expression in Liquid with string parameters

[bobwilkinson]

I am trying to write a section of conditional logic in the sql: section of a derived_table using a parameter. My strong preference is to use a string parameter to avoid using arbitrary numbers to control the logic.

This is the non-working version. No matter what value of the parameter is selected, the Liquid always resolves to the ‘else’ case. I have tried every different variant of reference a parameter that I have found online.

          where status = status_lookup.id and 

            {% if period_week_filter._parameter_value == 'before_next' %}

              week_index < 6

            {% else %}

              week_index < 2

            {% endif %};;

the parameter definition is:

  parameter:period_week_filter {

    type: string

    allowed_value: {

      value: "before_next"

    }

    allowed_value: {

      value: "before_last"

      }

    default_value: "before_next"

  }
 

The same code works fine, however, if I switch over to a number type parameter.

          where status = status_lookup.id and 

            {% if period_week_filter._parameter_value == '1' %}

              week_index < 6

            {% else %}

              week_index < 2

            {% endif %};;
 

the corresponding parameter definition is:

  parameter:period_week_filter {

    type: number

    allowed_value: {

      label: "before_next"

      value: "1"

    }

    allowed_value: {

      label: "before_last"

      value: "2"

      }

    default_value: "before_next"

  }
 

Please help - Thanks!