问题
in SQLite3, say i have this simple table
rowid value1 value2
(int) (float) (float)
1 15.3 20.2
2 17.8 30.5
3 15.8 25.3
4 16.1 48.0
How could I select those rows where the values are:
15.0 >= value1 <= 16.5 - effectively selecting rows 1,2 & 3
further how can i refine adding to the first criteria this to ALSO 20.0 >= value2 <= 37.0 - selecting then only row 1 & 3?
Your help is highly appreciated
回答1:
I believe your first logic is not correct, for if value1 is less than 15, it will also be less than 16.5, but just change the operators:
Select * from SimpleTable where value1 <= 15.0 and value1 <= 16.5;
Maybe you meant:
Select * from SimpleTable where value1 >= 15.0 and value1 <= 16.5;
Again (considering the adjusted logic):
Select * from SimpleTable where value1 >= 15.0 and value1 <= 16.5 and value2 >= 20.0 and value2 <= 37.0;
You might want to add and "order by" clause if you want your results sorted.
回答2:
Simply execute the SQL command below :
select id, value1, value2 FROM <table name> WHERE value1 >= 15.0 AND value1 <= 16.5 AND value2 >= 20.0 AND value2 <= 37.0
来源：https://stackoverflow.com/questions/8313777/sqlite3-select-field-by-numeric-range