How to Solve 2i + 2i to Get C in PostgreSQL

It looks like you want to add two measurements given in inches ("2in" + "2in") and get the result in centimeters (abbreviated as "C" or "cm"), using PostgreSQL.

However, PostgreSQL itself doesn't have built-in support for units like '2in'. So you need to parse the values, convert inches to a numeric value, add them, and then convert the sum to centimeters.

Step-by-step solution:

1. Parse the measurements: Extract the numeric part (2) from the string '2in'. You can use string functions or regular expressions.
2. Sum the values: Add the two numbers to get 4 inches.
3. Convert inches to centimeters: Multiply the total inches by 2.54 (since 1 inch = 2.54 cm).

Example PostgreSQL query:

WITH measurements AS (  
  SELECT '2in' AS measure1, '2in' AS measure2
), parsed AS (  
  SELECT 
    CAST(REGEXP_REPLACE(measure1, '[^0-9.]', '', 'g') AS numeric) AS val1,
    CAST(REGEXP_REPLACE(measure2, '[^0-9.]', '', 'g') AS numeric) AS val2
  FROM measurements
)
SELECT 
  val1 + val2 AS total_inches,
  (val1 + val2) * 2.54 AS total_centimeters
FROM parsed;

Explanation:

• REGEXP_REPLACE(measure1, '[^0-9.]', '', 'g') removes all characters except numbers and the decimal point to isolate the numeric part.
• The numeric parts are cast to numeric type for arithmetic.
• The inches are added to get total inches.
• The total inches are multiplied by 2.54 to convert to centimeters.

Result:

• total_inches = 4
• total_centimeters = 10.16

Therefore, "2in + 2in" equals 10.16 cm.