Results of 1 - 10 of about 76 for Process (0.001 sec.)
- Concurrency 14739
- Handling Concurrency Single Process In in-process mode, DuckDB has two configurable options for concurrency: Read-write mode: one process can both read and write to the database. Read-only mode: multiple processes can read from the database
..., but no processes can write ( access_mode = 'READ_ONLY' ). When using read-write mode, DuckDB supports multiple writer threads using a com...bination of MVCC (Multi-Version Concurrency Control) and optimistic concurrency control (see Concurrency within a Single Process ), but all within that single writer process. The reason for this concurrency model is to allow for the caching of data in...e catalog, and other items so that subsequent queries on the same connection are faster. Concurrency Model within a Single Process DuckDB supports concurrency within a single process according to the following rules. As long as there are no write confli... - https://man.mtool.work/duckdb/2.0/connect/concurrency.html
- Out of Memory Errors 11359
- DuckDB has a state of the art out-of-core query engine that can spill to disk for larger-than-memory processing. We continuously strive to improve DuckDB's scalability and prevent out of memory errors whenever possible. That said, you may s
...of size 256.0 KiB (476.7 MiB/476.8 MiB used) OOM Reaper (Linux) Many Linux distributions have an OOM killer or OOM reaper process whose goal is to prevent memory overcommitment. If the OOM reaper killed your process, you often see the following message...t more detailed information, check the diagnostic messages using the dmesg command (you may need sudo ): sudo dmesg If the process was killed by the OOM killer/reaper, you will find an entry like this: [Fri Apr 18 02:04:10 2025] Out of memory: Killed pr... - https://man.mtool.work/duckdb/2.0/guides/troubleshooting/oom_errors.html
- Glossary of Terms 10279
- This page contains a glossary of a few common terms used in DuckDB. Terms In-Process Database Management System The DBMS runs in the client application's process instead of running as a separate process, which is common in the traditional c
... - https://man.mtool.work/duckdb/2.0/guides/glossary.html
- SQLite Extension 9475
- The SQLite extension allows DuckDB to directly read and write data from a SQLite database file. The data can be queried directly from the underlying SQLite tables. Data can be loaded from SQLite tables into DuckDB tables, or vice versa. Ins
...modify a SQLite database while DuckDB or SQLite reads or modifies the same database from a different thread or a separate process. More than one thread or process can read the SQLite database at the same time, but only a single thread or process can wr...ite to the database at one time. Database locking is handled by the SQLite library, not DuckDB. Within the same process, SQLite uses mutexes. When accessed from different processes, SQLite uses file system locks. The locking mechanisms also d...e database: Option Description Default BUSY_TIMEOUT Time in milliseconds to wait when the SQLite file is locked by another process before returning a database is locked error. Set to 0 to fail immediately. 5000 JOURNAL_MODE SQLite journaling mode , e.g.... - https://man.mtool.work/duckdb/2.0/core_extensions/sqlite.html
- Crashes 9212
- DuckDB is thoroughly tested via an extensive test suite. However, bugs can still occur and these can sometimes lead to crashes. This page contains practical information on how to troubleshoot DuckDB crashes. Types of Crashes There are a few
...major types of crashes: Termination signals: The process stops with a SIGSEGV (segmentation fault), SIGABRT , etc.: these should never occur. Please submit an issue . Internal err...are cases, DuckDB can crash due to memory exhaustion. This crash can also be a symptom of the operating system killing the process. For example, many Linux distributions run an OOM reaper or OOM killer process , which kills processes to free up their me...triggers the crash is a good basis for a minimal reproducible example. If the multi-step approach works and the multi-step process no longer crashes, try to reconstruct the original query and observe which step reintroduces the error. In both cases, you... - https://man.mtool.work/duckdb/2.0/guides/troubleshooting/crashes.html
- DBine SQL Editor 8672
- DBine is a free, open-source (Apache 2.0) desktop database manager for Windows, macOS, and Linux that works with 130+ databases and cloud services. Besides a SQL editor, it includes notebooks, charts built from query results, and schema com
...ry database. Click Test connection to confirm the file can be opened, then click Save and connect . DuckDB allows only one process to open a database file for writing at a time. If another process (for example, the DuckDB CLI) has the file open, close i... - https://man.mtool.work/duckdb/2.0/guides/sql_editors/dbine.html
- VisuaLeaf SQL Editor 8672
- VisuaLeaf is a cross-platform desktop database client for Windows, macOS, and Linux. Besides a SQL editor, it includes a visual query builder, entity-relationship diagrams, and charts built from query results. VisuaLeaf ships with the DuckD
...click New DB . Click Test Connection to confirm the file can be opened, then click Save & Connect . DuckDB allows only one process to open a database file for writing at a time. If another process (for example, the DuckDB CLI) has the file open, close i... - https://man.mtool.work/duckdb/2.0/guides/sql_editors/visualeaf.html
- Troubleshooting 8395
- Troubleshooting Running EXPLAIN Renders Newlines In Python, the output of the EXPLAIN statement contains hard line breaks ( \n ): In [1]: import duckdb ...: duckdb.sql("EXPLAIN SELECT 42 AS x") Out[1]: ┌───────────────┬─────────────────────
...s fatal exception: access violation Current thread 0x0000311c (most recent call first): File "<stdin>", line 1 in <module> Process finished with exit code -1073741819 (0xC0000005) The problem is likely caused by using an outdated Microsoft Visual C++ (M...the number of CPU cores, at most 256. Every duckdb.connect() to an unnamed in-memory database starts a new database, so a process that opens many of them runs many threads. To start fewer, set async_threads when connecting: import duckdb con = duckdb.c...T max_temp_directory_size = '10GB'") Arrow Readers Hang on Windows after a Subinterpreter Was Created On Windows, once the process has created a subinterpreter, a query that scans a pyarrow.RecordBatchReader whose batches come from a Python generator ca... - https://man.mtool.work/duckdb/2.0/clients/python/known_issues.html
- Securing Extensions 8395
- DuckDB has a powerful extension mechanism, which has the same privileges as the user running DuckDB's (parent) process. This introduces security considerations. Therefore, we recommend reviewing the configuration options listed on this page
...ecurity-related configuration settings lock themselves , i.e., it is only possible to restrict capabilities in the current process. For example, attempting the following configuration changes will result in an error: SET allow_community_extensions = fal...s, but require that the source code of extensions is available . We do take over the complete build, sign and distribution process. Note that this is a step up from pip and npm that allow uploading arbitrary binaries but a step down from reviewing every... - https://man.mtool.work/duckdb/2.0/operations_manual/securing_duckdb/securing_ext...
- Securing DuckDB 8131
- DuckDB is a powerful analytical database engine. It can read and write files, access the network, load extensions, and use system resources. Like any powerful tool, these capabilities require appropriate configuration when working with sens
...ndboxing Run DuckDB in an isolated container (e.g., Docker with restricted capabilities) Use a virtual machine or separate process with minimal privileges Apply operating system-level sandboxing Use network isolation to prevent data exfiltration Impleme...such as new file formats, functions, and remote file system access. Extensions run with the same privileges as the DuckDB process itself, so they warrant careful consideration in security-sensitive environments. Autoloading DuckDB can automatically loa...ions entirely: SET allow_community_extensions = false; Serving DuckDB over the Network With the quack extension , a DuckDB process can act as a server ( CALL quack_serve(...) or duckdb -serve ). A Quack server exposes the full SQL surface of the instanc... - https://man.mtool.work/duckdb/2.0/operations_manual/securing_duckdb/overview.htm...
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