Results of 1 - 10 of about 73 for defined (0.002 sec.)
- DuckDB_% Metadata Functions 13624
- DuckDB offers a collection of table functions that provide metadata about the current database. These functions reside in the main schema and their names are prefixed with duckdb_ . The resultset returned by a duckdb_ table function may be
...ment A comment created by the COMMENT ON statement . VARCHAR internal true if this column is built-in, false if it is user-defined. BOOLEAN column_default The default value of the column (expressed in SQL) VARCHAR is_nullable true if the column can hold...contains the constraint. BIGINT schema_name The SQL name of the schema that contains the table on which the constraint is defined. VARCHAR schema_oid Internal identifier of the schema object that contains the table on which the constraint is defined. B...IGINT table_name The SQL name of the table on which the constraint is defined. VARCHAR table_oid Internal identifier (name) of the table object on which the constraint is defined. BIGINT constraint_in... - https://man.mtool.work/duckdb/2.0/sql/meta/duckdb_table_functions.html
- QUALIFY Clause 11891
- The QUALIFY clause is used to filter the results of WINDOW functions . This filtering of results is similar to how a HAVING clause filters the results of aggregate functions applied based on the GROUP BY clause . The QUALIFY clause avoids t
...DER BY . Examples Each of the following examples produce the same output, located below. Filter based on a window function defined in the QUALIFY clause: SELECT schema_name, function_name, -- In this example the function_rank column in the select clause...tions() QUALIFY row_number() OVER (PARTITION BY schema_name ORDER BY function_name) < 3; Filter based on a window function defined in the SELECT clause: SELECT schema_name, function_name, row_number() OVER (PARTITION BY schema_name ORDER BY function_nam...e) AS function_rank FROM duckdb_functions() QUALIFY function_rank < 3; Filter based on a window function defined in the QUALIFY clause, but using the WINDOW clause: SELECT schema_name, function_name, -- In this example the function_ran... - https://man.mtool.work/duckdb/2.0/sql/query_syntax/qualify.html
- TPC-H Extension 9991
- The tpch extension implements the data generator and queries for the TPC-H benchmark . Installing and Loading The tpch extension is shipped by default in some DuckDB builds, otherwise it will be transparently autoloaded on first use. If you
...used) sf DOUBLE Scale factor step UINTEGER Defines the partition to be generated, indexed from 0 to children - 1. Must be defined when the children arguments is defined suffix VARCHAR Append the suffix to table names Pre-Generated Datasets Pre-generate...mpliant datasets, use the tpchgen-cli project . Limitation The tpch(⟨query_id⟩) function runs a fixed TPC-H query with pre-defined bind parameters (a.k.a. substitution parameters). It is not possible to change the query parameters using the tpch extensi... - https://man.mtool.work/duckdb/2.0/core_extensions/tpch.html
- CREATE MACRO Statement 9809
- The CREATE MACRO statement defines a named, callable SQL expression as a database schema object. Macros may declare parameters, which can be referenced by its expression. Once a macro is created, it may be called by referencing its name and
...definition of a parameter that does not have a default value. In other words, parameters without default values have to be defined "in the front"; any parameters with default values appear "at the back". Multiple parameter declarations are separated fro...led 'overloads'), each having its own parameter list, AS keyword, and expression. Note that all of the implementations are defined in the same CREATE MACRO statement: it is not possible to add, remove, or alter individual implementations after the macro...elf: for a single macro, all of its implementations are either scalar or TABLE . When overloading table functions that are defined using a SELECT statement as expression, you will probably need to wrap the SELECT statement in parentheses. Calling Macros... - https://man.mtool.work/duckdb/2.0/sql/statements/create_macro.html
- Go Client 9292
- The latest stable release of the DuckDB Go client bundles DuckDB 2.0.0. Its own version tag encodes that DuckDB version; see Versioning below. The DuckDB Go client, duckdb-go , is a SQL driver that conforms to Go's built-in database/sql int
...o SQL database. On top of database/sql , the client adds DuckDB-specific interfaces for the Appender , Apache Arrow , user-defined functions , and profiling . This page focuses on installation. The other pages in this section cover connecting and each f...med duckdb with database/sql . Code that calls the client's own types and functions directly, such as the Appender or user-defined functions, imports the package under its duckdb name instead of with the blank identifier: import "github.com/duckdb/duckd...ly from Parquet, CSV, and JSON files. Handle Results — the Apache Arrow interface for columnar result exchange. Write User Defined Functions — scalar and table user-defined functions, and replacement scans. Profile and Monitor — query profiling and logg... - https://man.mtool.work/duckdb/2.0/clients/go/overview.html
- Constraints 9124
- In SQL, constraints can be specified for tables. Constraints enforce certain properties over data that is inserted into a table. Constraints can be specified along with the schema of the table as part of the CREATE TABLE statement . In cert
...nforce this property efficiently, an ART index is automatically created for every primary key or unique constraint that is defined in the table. Primary key constraints and unique constraints are identical except for two points: A table can only have on...e primary key constraint defined, but many unique constraints A primary key constraint also enforces the keys to not be NULL . CREATE TABLE students (id IN...table To enforce this property efficiently, an ART index is automatically created for every foreign key constraint that is defined in the table. Warning Indexes have certain limitations that might result in constraints being evaluated too eagerly, leadi... - https://man.mtool.work/duckdb/2.0/sql/constraints.html
- Handle Results 8943
- Overview Beyond the standard JDBC ResultSet , the DuckDB driver can hand results to Apache Arrow , stream large results instead of materializing them, and expose raw columnar data chunks. This page covers each of these result-handling optio
...d by the JDBC ResultSet interface. Chunk contents are read through the same DuckDBDataChunkReader API that is used by user-defined functions . Call query() on a DuckDBPreparedStatement to obtain a DuckDBChunkedResult , then advance through the chunks wi...s remain 1-based, following the JDBC convention, while chunk columns and rows are 0-based, matching the C API and the user-defined function interfaces. The chunked result API currently supports basic data types only. Composite types such as LIST and STR...sultSet accessors. Define Functions — the DuckDBDataChunkReader API shared with chunked results is also used to write user-defined functions. Define Connections — the jdbc_stream_results option that enables result streaming. C API — the duckdb_fetch_chu... - https://man.mtool.work/duckdb/2.0/clients/java/result_handling.html
- Bitstring Functions 8775
- This section describes functions and operators for examining and manipulating BITSTRING values. Bitstrings must be of equal length when performing the bitwise operands AND, OR and XOR. When bit shifting, the original length of the string is
...d on all bitstrings in a given expression. bitstring_agg(arg) Returns a bitstring with bits set for each distinct position defined in arg . bitstring_agg(arg, min, max) Returns a bitstring with bits set for each distinct position defined in arg . All po...nd dense values. bitstring_agg(arg, min, max) | Description | Returns a bitstring with bits set for each distinct position defined in arg . All positions must be within the range [ min , max ] or an Out of Range Error will be thrown. | | Example | bitst... - https://man.mtool.work/duckdb/2.0/sql/functions/bitstring.html
- Information Schema 8775
- The views in the information_schema are SQL-standard views that describe the catalog entries of the database. These views can be filtered to obtain information about a specific column or table. DuckDB's implementation is based on PostgreSQL
...s that are used in the check expression. For a not-null constraint, this view identifies the column that the constraint is defined on. For a foreign key constraint, this view identifies the columns that the foreign key references. For a unique or primar...not available in DuckDB. VARCHAR NULL reference_generation Applies to a feature not available in DuckDB. VARCHAR NULL user_defined_type_catalog If the table is a typed table, the name of the database that contains the underlying data type (always the cu...rrent database), else NULL . Currently unimplemented. VARCHAR NULL user_defined_type_schema If the table is a typed table, the name of the schema that contains the underlying data type, else NULL . Curr... - https://man.mtool.work/duckdb/2.0/sql/meta/information_schema.html
- Rust Client 8426
- Installation To use the DuckDB Rust client, visit the Rust installation page . The latest stable version of the DuckDB Rust client is 2.0.0. The DuckDB Rust client, duckdb-rs , is an ergonomic wrapper over the DuckDB C API that exposes an i
...erface modeled on rusqlite . It supports type-safe queries, bulk loading with the Appender, Apache Arrow interchange, user-defined functions, and building DuckDB extensions in Rust. This page focuses on installation. The other pages in this section cove...eading directly from Parquet, CSV, and JSON files. Handle Results — Apache Arrow and Polars result interchange. Write User Defined Functions — user-defined scalar and table functions, and loadable extensions. Profile and Monitor — query profiling and in... - https://man.mtool.work/duckdb/2.0/clients/rust/overview.html
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