Results of 1 - 7 of about 7 for helpful (0.002 sec.)
- Advanced Installation Methods 13086
- Downloading Extensions Directly from S3 Downloading an extension directly can be helpful when building a Lambda service or container that uses DuckDB. DuckDB extensions are stored in public S3 buckets, but the directory structure of those b
... - https://man.mtool.work/duckdb/2.0/extensions/advanced_installation_methods.html
- Indexing 9742
- DuckDB has two types of indexes: zonemaps and ART indexes. Zonemaps DuckDB automatically creates zonemaps (also known as min-max indexes) for the columns of all general-purpose data types . Operations like predicate pushdown into scan opera
...lective filters, it is best to pre-order data by those columns when inserting it. Even an imperfect ordering will still be helpful. The best case of ordered data commonly arises with DATETIME columns. Microbenchmark: The Effect of Ordering For an exampl... - https://man.mtool.work/duckdb/2.0/guides/performance/indexing.html
- File Formats 9087
- Handling Parquet Files DuckDB has advanced support for Parquet files, which includes directly querying Parquet files . When deciding on whether to query these files directly or to first load them to the database, you need to consider severa
...ilter condition. DuckDB will only need to read the folders and files that meet the filter criteria. This can be especially helpful when querying remote files. More Tips on Reading and Writing Parquet Files For tips on reading and writing Parquet files,... - https://man.mtool.work/duckdb/2.0/guides/performance/file_formats.html
- Tuning Workloads 8415
- DuckDB aims to perform well out of the box, so most workloads do not require any tuning. When tuning is worthwhile, there is no single configuration or magic number that is optimal for every workload: the right settings depend on what you a
...ssible to parallelize in all cases. Making multiple connections can process more operations concurrently. This can be more helpful if DuckDB is not CPU limited, but instead bottlenecked by another resource like network transfer speed. Persistent vs. In-... - https://man.mtool.work/duckdb/2.0/guides/performance/how_to_tune_workloads.html
- INSERT Statement 8415
- The INSERT statement inserts new data into a table. Examples Insert the values 1, 2, 3 into tbl : INSERT INTO tbl VALUES (1), (2), (3); Insert the result of a query into a table: INSERT INTO tbl SELECT * FROM other_tbl; Insert values into t
...RETURNING *, i * j AS i_times_j; i j i_times_j 2 3 6 The next example shows a situation where the RETURNING clause is more helpful. First, a table is created with a primary key column. Then a sequence is created to allow for that primary key to be incre... - https://man.mtool.work/duckdb/2.0/sql/statements/insert.html
- FROM and JOIN Clauses 7742
- The FROM clause specifies the source of the data on which the remainder of the query should operate. Logically, the FROM clause is where the query starts execution. The FROM clause can contain a single table, a combination of multiple table
...OM generate_series(0, 1) t(i), LATERAL (SELECT i + 10 UNION ALL SELECT i + 100) t2(j); i j 0 10 1 11 0 100 1 101 It may be helpful to think about LATERAL as a loop where we iterate through the rows of the first subquery and use it as input to the second... - https://man.mtool.work/duckdb/2.0/sql/query_syntax/from.html
- Geometry Data Type 7070
- Name Description GEOMETRY Geospatial entity The GEOMETRY data type is used to store and manipulate geometric objects, such as points, lines, and polygons. The GEOMETRY type was part of the spatial extension but became a built-in data type i
...oordinate Reference System (CRS) that defines how the coordinates relate to real-world locations on the Earth's surface. A helpful analogy is to think of CRSs as the equivalent of "time zones", but for geospatial data. Just like how time zones define ho... - https://man.mtool.work/duckdb/2.0/sql/data_types/geometry.html
PREV
1
NEXT
DuckDB 2.0 Documentation / man.mtool.work