Example data in a weight
column (from 3 rows of data)
+-------------------------+
| weight |
+-------------------------+
| Pump:398kg Motor:0kg |
| Pump:448# Motor:997# |
| Pump:355kg Motor:2495kg |
+-------------------------+
Is there a way to extract the first number from column, and the 2nd number in the column separately?
Note
Pump:
Motor:
will always be in the middle #
or kg
, there are no others My goal is to split the numbers each into their own column
ie
UPDATE table set weight_pump = ?, weight_motor = ?
UPDATE table set weight_pump = 398, weight_motor = 0
I can solve this using PHP (SELECT each row, do REGEX to extract numbers, write back to the row)
But what I am looking for is a pure SQL solution, if such exists. Preferably a single SQL statement, if exists but I am not opposed to several statements or intermediate steps.
I have seen other answers but they focus on extracting a single number from SQL, I am seeking something more powerful.
Note: it can be also done in two steps (one for "kg", one for "#") to simplify query.
Here's a solution, using substring_index().
I like this function because it doesn't depend so much on specific character positions.
mysql> SELECT
SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(weight, ':', -2), 'kg', 1), '#', 1) AS weight_pump,
SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(weight, ':', -1), 'kg', 1), '#', 1) AS weight_motor
FROM MyTable;
Output:
+-------------+--------------+
| weight_pump | weight_motor |
+-------------+--------------+
| 398 | 0 |
| 448 | 997 |
| 355 | 2495 |
+-------------+--------------+
This works with UPDATE too:
mysql> UPDATE MyTable
SET weight_pump = SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(weight, ':', -2), 'kg', 1), '#', 1),
weight_motor = SUBSTRING_INDEX(SUBSTRING_INDEX(SUBSTRING_INDEX(weight, ':', -1), 'kg', 1), '#', 1);
Read more about this function here: http://dev.mysql.com/doc/refman/5.7/en/string-functions.html#function_substring-index
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