![]() You can check this using the explain SQL command, e.g. The optimiser can also potentially make use of the index for case-insensitive searching and matching on the column. Sqlite> select Text_Value from Test order by Text_Value desc Sqlite> select Text_Value from Test order by Text_Value Sqlite> select Text_Value from Test where Text_Value = 'B' For example:Įxpressions involving Test.Text_Value should now be case insensitive. You can specify collate nocase when you create an index as well. WHERE name = 'someone' COLLATE NOCASEĪdditionaly, in SQLite, you can indicate that a column should be case insensitive when you create the table by specifying collate nocase in the column definition (the other options are binary (the default) and rtrim see here). Please show your love and support by sharing this post.You can use COLLATE NOCASE in your SELECT query: SELECT * FROM. This would have performance issues, especially for larger tables. Therefore, it ends up doing a full-scan going through all rows and converting them to upper or lower case (depending on the function you use) before doing the comparison. SQLite does not make use of an index when using UPPER() or LOWER() functions. WHERE LOWER(`title`) = LOWER('lorem ipsum') WHERE UPPER(`title`) = UPPER('lorem ipsum') We could use UPPER() or LOWER() function on both sides of string comparison so that we have the same case on either side. ![]() Making the Compared Strings the Same Case ![]() Using LIKE operator may have performance issues, especially for large tables, as SQLite will do a full-scan of the rows unless the column you're using LIKE on has a COLLATE NOCASE index. Therefore, for English characters we could use LIKE for case-insensitive comparison like so:Īnd for non-english characters we could use a unicode-aware LIKE (for example, from the ICU extension). db. All I want to do is grab the stuff in alphabetical order and ignore the capital letters. # output: SEARCH TABLE post USING INDEX IDX_BLOG_POST_TITLE (title=?)Īs evident from the example above, when COLLATE NOCASE index is present, the query does not scan all rows.Ĭase-Insensitive Comparisons With the LIKE Operatorīy default, the SQLite LIKE operator is case-insensitive for ASCII characters (which covers all english language letters), and case-sensitive for unicode characters that are beyond the ASCII range. How to use SQL Order By statement to sort results case insensitive (3 answers) Closed 7 years ago. ![]() However, with the index added, we get the following output with EXPLAIN QUERY PLAN: To demonstrate this, let's do EXPLAIN QUERY PLAN on our query:ĮXPLAIN QUERY PLAN SELECT * FROM `blog_post` WHERE `title` = 'lorem ipsum' Īs you can see in the example above, SQLite does a full-table scan and visits all rows in the table when we don't have an index. Without a COLLATE NOCASE index, our queries will do a full table scan. Our index with UTF8CI encoding cannot be used: SQLite has no information about the collation of the index. This executes normally and gives the result as usual case-sensitive (binary) sort. SELECT FROM testtbl ORDER BY Name COLLATE BINARY. To optimize lookups, we can create an index with COLLATE NOCASE for the column with case-insensitive strings. To avoid this, you can use the following SQL: SQL. For example, the following query will do a case-insensitive comparison now as the column itself is defined as COLLATE NOCASE: Now, we won't have to explicitly use COLLATE NOCASE in our queries. Title VARCHAR(25) NOT NULL COLLATE NOCASE WHERE `title` COLLATE NOCASE IN ('lorem ipsum', 'fusce vitae')Īlternatively, we could declare the column itself as case-insensitive by adding COLLATE NOCASE in the CREATE TABLE column definition like so: For example, to use it with the IN operator, we could do the following: The COLLATE operator can be used with other operators as well. WHERE `title` = 'lorem ipsum' COLLATE NOCASE The COLLATE operator can be used with the built-in NOCASE collating function to do case-insensitive comparisons, like so: You could use the SQLite ICU (International Components for Unicode) extension to support case mapping for full range of unicode characters for the following SQLite operations/functions:Ĭase-Insensitive Comparisons Using the COLLATE Operator This means that only case mapping for letters in the English language are supported by default. For examples in this article, let's suppose we have the following table:Ĭase-Insensitive Comparison for Non-English Charactersīefore we learn how to do case-insensitive comparisons, it is important to know that by default, SQLite only supports string comparisons for ASCII characters. In this article, we'll have a look at different ways of doing a case-insensitive string comparison in SQLite.
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