How do I get LIKE and COUNT to return the number of rows less than a value not in the row?
For example:
SELECT COUNT(ID) FROM My_Table
WHERE ID <
(SELECT ID FROM My_Table
WHERE ID LIKE '%4'
ORDER BY ID LIMIT 1)
My_Table:
X ID Y
------------------------
| | A1 | |
------------------------
| | B2 | |
------------------------
| | C3 | |
------------------------ -----Page 1
| | D3 | |
---------------------开发者_Go百科---
| | E3 | |
------------------------
| | F5 | |
------------------------ -----Page 2
| | G5 | |
------------------------
| | F6 | |
------------------------
| | G7 | | -----Page 3
There is no data ending in 4 but there still are 5 rows that end in something less than "%4
".
However, in this case were there is no match, so SQLite only returns 0
I get it is not there but how do I change this behavior to still return number of rows before it, as if it was there?
Any suggestions?
Thank You.
SELECT COUNT(ID) FROM My_Table
WHERE ID < (SELECT ID FROM My_Table
WHERE SUBSTRING(ID, 2) >= 4
ORDER BY ID LIMIT 1)
Assuming there is always one letter before the number part of the id
field, you may want to try the following:
SELECT COUNT(*) FROM my_table WHERE CAST(substr(id, 2) as int) <= 4;
Test case:
CREATE TABLE my_table (id char(2));
INSERT INTO my_table VALUES ('A1');
INSERT INTO my_table VALUES ('B2');
INSERT INTO my_table VALUES ('C3');
INSERT INTO my_table VALUES ('D3');
INSERT INTO my_table VALUES ('E3');
INSERT INTO my_table VALUES ('F5');
INSERT INTO my_table VALUES ('G5');
INSERT INTO my_table VALUES ('F6');
INSERT INTO my_table VALUES ('G7');
Result:
5
UPDATE: Further to the comment below, you may want to consider using the ltrim()
function:
The
ltrim(X,Y)
function returns a string formed by removing any and all characters that appear inY
from the left side ofX
.
Example:
SELECT COUNT(*)
FROM my_table
WHERE CAST(ltrim(id, 'ABCDEFGHIJKLMNOPQRSTUVWXYZ') as int) <= 4;
Test case (adding to the above):
INSERT INTO my_table VALUES ('ABC1');
INSERT INTO my_table VALUES ('ZWY2');
New Result:
7
In MySQL
that would be:
SELECT COUNT(ID)
FROM My_Table
WHERE ID <
(
SELECT id
FROM (
SELECT ID
FROM My_Table
WHERE ID LIKE '%4'
ORDER BY
ID
LIMIT 1
) q
UNION ALL
SELECT MAX(id)
FROM mytable
LIMIT 1
)
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