How to change the collation of sqlite3 database to sort case insensitively?

问题

I have a query for sqlite3 database which provides the sorted data. The data are sorted on the basis of a column which is a varchar column "Name". Now when I do the query

select * from tableNames Order by Name;

It provides the data like this.

    Pen
    Stapler
    pencil

Means it is considering the case sensitive stuff. The way I want is as follows

    Pen
    pencil
    Stapler

So what changes should I make in sqlite3 database for the necessary results?

Related How to set Sqlite3 to be case insensitive when string comparing?

回答1:

The SQLite Datatypes documentation discusses user-defined collation sequences. Specifically you use COLLATE NOCASE to achieve your goal.

They give an example:

CREATE TABLE t1(
    a,                 -- default collation type BINARY
    b COLLATE BINARY,  -- default collation type BINARY
    c COLLATE REVERSE, -- default collation type REVERSE
    d COLLATE NOCASE   -- default collation type NOCASE
);

and note that:

-- Grouping is performed using the NOCASE collation sequence (i.e. values -- 'abc' and 'ABC' are placed in the same group). SELECT count(*) GROUP BY d FROM t1;

回答2:

To sort it Case insensitive you can use ORDER BY Name COLLATE NOCASE

回答3:

select * from tableNames Order by lower(Name);

Michael van der Westhuizen explains in his comment below why this is not a good way. I am leaving this answer up so as to preserve his comment and to serve as a warning to others who might have the same 'bright' idea I had ;-)

回答4:

Use this statement in your SQLite database:

PRAGMA case_sensitive_like = false

来源：https://stackoverflow.com/questions/1188749/how-to-change-the-collation-of-sqlite3-database-to-sort-case-insensitively

标签

sql

sqlite

sql-order-by

case-insensitive