Why are my fields with division showing up as 0?

In certain dialects, including Postgres and Redshift, performing a calculation between integers (like dividing counts) will return an integer even if the result would be a decimal in normal math. For example, you might make measures like the following:

measure: sold_ratio {
    type: number
    sql: ${sold_count} / ${total_count} ;;
    value_format: "0.00" # Number with exactly 2 decimals (1.23)
}

measure: sold_percent {
    type: number
    sql: 100 * ${sold_count} / ${count} ;;
    value_format: "0.00"
}

However, when you run the measures in an Explore, the Sold Ratio column returns zero, and the Sold Percent column does not have its decimal places populated. This is not correct:

Inventory Items Sold Percent	Inventory Items Sold Ratio	Inventory Items Count	Inventory Items Sold Count
48.00	0	1,165,224	560,223

The solution: Cast your field as a floating-point number

If the calculation is multiplied by a non-integer, the values will cast as floats, and decimals will be returned as expected. You can multiply the numerator by a decimal number (like 1.0 or 100.0) to force SQL to return a decimal result:

measure: sold_ratio {
    type: number
    sql: 1.0 * ${sold_count} / ${total_count};;
    value_format: "0.00"
}

measure: sold_percent {
    type: Number
    sql: 100.0 * ${sold_count} / ${count};;
    value_format: "0.00"
}

The resulting Explore Data table now displays the expected results:

Inventory Items Sold Percent	Inventory Items Sold Ratio	Inventory Items Count	Inventory Items Sold Count
48.08	0.48	1,165,224	560,223