![]() I'm aware any solution you'll come up with will take time to implement, especially since we're hitting a limitation of SQLite (compared to other database backends). Having a single flag on an attribute is way more practical than adding the same code over and over again to every query using that attribute. I think the case_insensitive parameter would be more useful, especially for attributes we want to be "user-searchable". If I wanted to use an SQL-like syntax I'd use the raw_sql/ select_by_sql functions Pony is already providing us with. Plus it would defeat the purpose of providing a pythonic way to write queries. lower() to the operand one wants to use with in or startswith/ endswith. But I chose to design my database schemas to be case insensitive on some fields, knowing it wouldn't be consistent with the Python language, for the ease of use it brings.Īdding like and ilike functions would be the same as not adding or adding. I'm also well aware that string operations are case sensitive in Python. I totally understand and that's what I would expect when working with a backend-agnostic library. I think we can add direct support of like and ilike (case-insensitive like) functions to Pony, so instead of But in SQLite the function that implements LIKE operator does not receive information about collations of its arguments, so it is not possible for LIKE in SQLite to be case-insensitive only when it is necessary. In other databases, when LIKE operates on columns with case-insensitive collation, it provides case-insensitive result. These operations in Python are case-sensitive so it makes sense to keep them case-sensitive in query, so the result is the same as in Python. It is used for translation of Python string operations, like, in or startswith/ enswith. ![]() Because of this, in 0.7.5 we made LIKE case-sensitive for ASCII symbols in SQLite.Īlso, at this moment we don't provide LIKE operator directly in Pony. In other databases LIKE is case-sensitive for all symbols, except when special case-insensitive collation is specified. By default in SQLite LIKE is case-insensitive for ASCII symbols, but is case-sensitive for Unicode symbols. ![]() The default LIKE implementation in SQLite differs from another databases. See User-defined functions for details on overriding the implementation of the LIKE operator.Our goal is maximum possible compatibility between different databases, so the same Pony query returns the same result in all databases. You can easily make the LIKE operator case-sensitive by using the following pragma statement: PRAGMA case_sensitive_like = 1 It's only case-insensitive for the ASCII characters A through Z. Solution 1 You can also do ORDER BY TITLE COLLATE NOCASE. You can just convert everything to lowercase for the purposes of sorting: SELECT FROM NOTES ORDER BY LOWER (title) If you want to make sure that the uppercase ones still end up ahead of the lowercase ones, just add that as a secondary sort: SELECT FROM NOTES ORDER BY LOWER (title), title Share. The default implementation has the same semantics as the NOCASE collation. The LIKE operator in SQLite doesn't honor collations. ![]() Var count = (oCount is not null) ? (int)oCount : -1 Var oCount = quer圜ommand.ExecuteScalar() Var quer圜ommand = connection.CreateCommand() connection.CreateCollation("NOCASE", (x, y) => string.Compare(x, y, ignoreCase: true)) ![]() The full sample code is available on GitHub. db. All I want to do is grab the stuff in alphabetical order and ignore the capital letters. Normalize all strings to the same case, - does not matter lower or upper: SELECT FROM items WHERE LOWER(text) 'string in lower case' - 3. I want to use case insensitive comparison and pattern matching, and my database schemas are designed accordingly (tables aren't created by pony) using unicodeci collations on MySQL, citext on PostgreSQL and COLLATE NOCASE on SQLite. Use a NOCASE collation - (we will look at other ways for applying collations later): SELECT FROM items WHERE text 'String in AnY case' COLLATE NOCASE - 2. The following example shows overriding the NOCASE collation to support Unicode characters. How to use SQL Order By statement to sort results case insensitive (3 answers) Closed 7 years ago. Since version 0.7.4, LIKEs on SQLite are case sensitive.Is there a way to revert to the old behaviour other than adding. You can also define your own collating sequences or override the built-in ones using CreateCollation. CollationĬase-insensitive for ASCII characters A-Z SQLite includes three collating sequences by default. You can specify which collation to use when creating columns or per-operation in SQL queries. Collating sequences are used by SQLite when comparing TEXT values to determine order and equality. ![]()
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