Results of 1 - 10 of about 14 for event (0.002 sec.)
- Profile and Monitor 13163
- Overview The JDBC driver exposes several ways to observe a running or completed query: cancelling and timing out queries, polling query progress, retrieving profiling output, and emitting memory-usage events through Java Flight Recorder . T
...System.out.println(profile); } Memory Monitoring with JFR On a JFR-capable JVM , the driver can emit Java Flight Recorder events describing DuckDB's internal memory usage, so that any JFR-aware tool — JDK Mission Control, the jfr command line tool, c...mitted unless the application both sets the JDBC property on a connection and has an active JFR recording that enables the event. Enabling Emission Monitoring is opt-in per connection: set the jdbc_jfr_memory_monitor property to an identifier for the...connection's database instance. The value is an arbitrary label that is attached to every event as its component field, so that operators can attribute memory to logical components. An absent or empty value leaves moni... - https://man.mtool.work/duckdb/2.0/clients/java/profiling.html
- Writing to Iceberg 11955
- The DuckDB iceberg extension supports writing to Iceberg tables when an Iceberg catalog is attached. Writing to a table read directly from storage with iceberg_scan is not supported: the catalog is required to commit the new table metadata.
...lue1', 'property2' = 'value2' ); Tables can also be created from the result of a query: CREATE TABLE iceberg_catalog.sales.events_copy AS FROM iceberg_catalog.sales.events; Table properties can also be inspected and modified after creation, see Table...The UPDATE and DELETE statements are supported on both partitioned and unpartitioned tables: UPDATE iceberg_catalog.sales.events SET event_name = 'view' WHERE id = 1; DELETE FROM iceberg_catalog.sales.events WHERE event_time < TIMESTAMP '2026-01-01';...o a multiple of w for numeric columns). This is useful for prefix-based partitioning. CREATE TABLE iceberg_catalog.default.events ( event_id BIGINT, user_id BIGINT, country VARCHAR, event_time TIMESTAMP ) PARTITIONED BY (day(event_time), bucket(16, us... - https://man.mtool.work/duckdb/2.0/core_extensions/iceberg/writing_to_iceberg.htm...
- Window Functions 10222
- DuckDB supports window functions , which can use multiple rows to calculate a value for each row. Window functions are blocking operators , i.e., they require their entire input to be buffered, making them one of the most memory-intensive o
...syntax and use framing to restrict the range that the secondary ordering applies to. -- Compare each athlete's time in an event with the best time to date SELECT event, date, athlete, time, first_value(time ORDER BY time ASC) OVER w AS record_time, f...irst_value(athlete ORDER BY time ASC) OVER w AS record_athlete, FROM meet_results WINDOW w AS (PARTITION BY event ORDER BY datetime) ORDER BY ALL; Note that there is no comma separating the arguments from the ORDER BY clause. Nulls All...Boston 2019-01-04 3 ... ... ... Worcester 2019-01-02 1 Worcester 2019-01-03 2 Worcester 2019-01-04 3 ... ... ... Note that even though the function is computed with an ORDER BY clause, the result does not have to be sorted, so the SELECT also needs to... - https://man.mtool.work/duckdb/2.0/sql/functions/window_functions.html
- CREATE TRIGGER Statement 9452
- New The CREATE TRIGGER feature was introduced in DuckDB 2.0. The CREATE TRIGGER statement registers a trigger: a set of SQL statements that run automatically in response to INSERT , UPDATE , or DELETE events on a table. Examples Record ever
...results in an error. The two clauses cannot be combined. Multiple Triggers A table can have multiple triggers for the same event, as long as they have the same granularity (see Limitations ). They fire in the order in which they were created. Returnin...defined in the catalog can be listed with the duckdb_triggers() function : SELECT trigger_name, table_name, action_timing, event_manipulation, for_each FROM duckdb_triggers(); Dropping Triggers A trigger is dropped with DROP TRIGGER . The table the tr...supported on tables with FOR EACH ROW triggers. FOR EACH ROW and FOR EACH STATEMENT triggers cannot be mixed for the same event on the same table.... - https://man.mtool.work/duckdb/2.0/sql/statements/create_trigger.html
- Appender 8367
- Use an appender to insert rows that your Python code produces. It collects rows and writes them together in one SQL statement; this is called flushing. The with block below flushes on successful exit: import duckdb con = duckdb.connect() co
...e of the columns, list them in columns . The other columns take their default value, per row: con.execute("CREATE SEQUENCE event_ids") con.execute( "CREATE TABLE events (id INTEGER DEFAULT nextval('event_ids'), kind VARCHAR, note VARCHAR DEFAULT 'none...')" ) appender = con.appender("events", columns=["kind"]) appender.append_row("login") appender.append_row("logout") appender.flush() Updates, Upserts and Dele... - https://man.mtool.work/duckdb/2.0/clients/python/appender.html
- Write User Defined Functions 7929
- Overview The JDBC driver can register user-defined functions (UDFs) written in Java, including scalar functions and table functions. This page covers building and registering both, from the simple functional-interface overloads to the vecto
...kDBLogicalType dblType = DuckDBLogicalType.of(DuckDBColumnType.DOUBLE)) { DuckDBFunctions.scalarFunction() .withName("java_event_label") .withParameters(tsType, strType, dblType) .withReturnType(strType) .withVectorizedFunction((input, output) -> { in...Case() + " | " + input.vector(2).getDouble(row, 0.0d); output.setString(row, value); }); }) .register(conn); } SELECT java_event_label(TIMESTAMP '2026-04-04 12:00:00', 'launch', 4.5); The DuckDBDataChunkReader , its DuckDBReadableVector columns, and t... - https://man.mtool.work/duckdb/2.0/clients/java/functions.html
- Parquet Tips 7929
- Below is a collection of tips to help when dealing with Parquet files. Tips for Reading Parquet Files Use union_by_name When Loading Files with Different Schemas The union_by_name option can be used to unify the schema of files that have di
...n-overlapping between row groups, so that highly selective queries on those columns scan far fewer row groups: COPY (FROM 'events.parquet' ORDER BY event_time) TO 'events-sorted.parquet' (FORMAT parquet); This pairs well with a ROW_GROUP_SIZE that kee... - https://man.mtool.work/duckdb/2.0/data/parquet/tips.html
- CLI Charting with YouPlot 7929
- DuckDB can be used with CLI graphing tools to quickly pipe input to stdout to graph your data in one line. YouPlot is a Ruby-based CLI tool for drawing visually pleasing plots on the terminal. It can accept input from other programs by pipi
...h a quick curl from GitHub to see what a certain user has been up to lately. curl -sL "https://api.github.com/users/dacort/events?per_page=100" \ | duckdb -s "COPY (SELECT type, count(*) AS event_count FROM read_json('/dev/stdin') GROUP BY 1 ORDER BY...2 DESC LIMIT 10) TO '/dev/stdout' WITH (FORMAT csv, HEADER)" \ | uplot bar -d, -H -t "GitHub Events for @dacort"... - https://man.mtool.work/duckdb/2.0/guides/data_viewers/youplot.html
- Partitioned Writes 7824
- Examples Write a table to a Hive partitioned dataset of Parquet files: COPY orders TO 'orders' (FORMAT parquet, PARTITION_BY (year, month)); Write a table to a Hive partitioned dataset of CSV files, allowing overwrites: COPY orders TO 'orde
...options, but DuckDB performs an extra check for whether the file already exists and then regenerates the UUID in the rare event that it does (to avoid clashes). Handling Slashes in Columns To handle slashes in column names, use Percent-Encoding imple... - https://man.mtool.work/duckdb/2.0/data/partitioning/partitioned_writes.html
- DuckDB_% Metadata Functions 7702
- 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
...r is attached to. VARCHAR action_timing When the trigger fires relative to the triggering statement, e.g., AFTER . VARCHAR event_manipulation The event that fires the trigger: INSERT , UPDATE or DELETE . VARCHAR columns For UPDATE OF ⟨column⟩, ... tri... - https://man.mtool.work/duckdb/2.0/sql/meta/duckdb_table_functions.html
DuckDB 2.0 Documentation / man.mtool.work