![]() ![]() Specify resultSelector to calculate the final result from the context after iterating through all the rows. This can simplify the definition of functions like sum and count that only need to increment a number each row and return it. If no resultSelector is specified, the final state of the context is used as the result. This pattern allows the context to be a value type or immutable. Use the context to accumulate a final result. The func argument is invoked once per row. The seed argument specifies the initial state of the context. Define and override aggregate functions using CreateAggregate. connection.CreateFunction(Īggregate functions return a single, aggregated value for all the rows in a query. SQLite doesn't include a default implementation of the regexp function. The following example shows how to define the regexp function to enable its corresponding operator. Defining these scalar functions in your app will override the behavior of these operators. ![]() The following SQLite operators are implemented by corresponding scalar functions. ![]() Var command = connection.CreateCommand() => Math.PI * Math.Pow(radius, 2) * height) The following example shows how to add a scalar function to calculate the radius of a cylinder. Specify isDeterministic if your function is deterministic to allow SQLite to use additional optimizations when compiling queries. Specifying the state argument will pass that value into every invocation of the function. See Data types for a list of supported parameter and return types for the func argument. Define new scalar functions and override the built-in ones using CreateFunction. Scalar functions return a single, scalar value for each row in a query. Instead of having to learn a new dialect of SQL, you can just use the programming language of your app. SQLite however, runs in-process with your app. SQLite command-line interface (CLI, aka 'sqlite3.Most databases have a procedural dialect of SQL that you can use to define your own functions. Installation and UsageĮxamples below use the stats extension you can specify any other supported extension. If you are using SQLite shell on Windows ( sqlite.exe), its 64-bit version is available at. sqlean-macos-arm64.zip - for Apple silicon (ARM-based) macOSīinaries are 64-bit and require a 64-bit SQLite version.sqlean-macos-x86.zip - for Intel-based macOS.There are precompiled binaries for every OS: Vote for your favorites! We'll refactor and merge popular ones into the main set. zorder: map multidimensional data to a single dimension.unionvtab: union similar tables into one.uint: natural string sorting and comparison.stats2 and stats3: additional math statistics functions.spellfix: search a large vocabulary for close matches.pearson: Pearson correlation coefficient between two data sets.isodate: additional date and time functions.decimal, fcmp and ieee754: decimal and floating-point arithmetic.cron: match dates against cron patterns.compress and sqlar: compress / uncompress data.closure: navigate hierarchic tables with parent/child relationships.classifier: binary classifier via logistic regression.cbrt and math2: additional math functions and bit arithmetics.btreeinfo, memstat, recsize and stmt: various database introspection features.bloom: a fast way to tell if a value is already in a table.besttype: convert string value to numeric.Think of them as candidates for the standard library: They may be untested, poorly documented, too broad, too narrow, or without a well-thought API. These extensions haven't yet made their way to the main set. fuzzy: fuzzy string matching and phonetics.define: user-defined functions and dynamic sql.Think of them as the extended standard library for SQLite: They are tested, documented and organized into the domain modules with clear API. To achieve it, we split extensions that are too broad, merge the ones that are too narrow, refactor, add missing features, test, document, and do a ton of other small things. The goal is to create a well-thought set of domain modules with a convenient API. We do not try to gather all the existing extensions into one giant pile - that would not be very useful. sqlean brings them together, neatly packaged into domain modules, documented, tested, and built for Linux, Windows and macOS. ![]() There are a lot of SQLite extensions out there, but they are incomplete, inconsistent and scattered across the internet. SQLite authors see this as a feature rather than a problem, because SQLite has an extension mechanism in place. SQLite has few functions compared to other database management systems. ![]()
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