Database(167 terms)
A full list of the Database terms and explanations covered by ITBGM.
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ACID Properties Transactions ☆ The umbrella name for the four properties a transaction should satisfy.
Apache Iceberg Analytics Platforms ☆ An open table format that lets you work with huge data-lake tables the way you would a relational database.
AVG Function SQL ☆ An aggregate function that computes the average of a column's values.
Backup Operations Management ☆ Keeping a separate copy of data stored elsewhere.
BASE Properties NoSQL ☆ A NoSQL design philosophy that prioritizes always being responsive and eventually reaching consistency.
BETWEEN Operator SQL ☆ An operator that checks whether a value falls within a specified range.
B-Tree Index Performance ☆ A tree-structured indexing method adopted as the default in most relational databases.
Buffer Pool Performance ☆ A region that caches disk data in memory to speed up access.
Cache-Aside Performance ☆ A caching pattern where the application reads from and writes to the cache and the database separately.
Candidate Key RDBMS Fundamentals ☆ A column (or set of columns) that can uniquely identify a row and could serve as the primary key.
CAP Theorem NoSQL ☆ The theory that consistency, availability, and partition tolerance can't all be satisfied at once.
CASE Expression SQL ☆ Conditional logic usable within SQL that returns different values based on conditions.
Cassandra Major Products ☆ A column-oriented NoSQL database that manages large-scale data in a distributed fashion.
CDC (Change Data Capture) Analytics Platforms ☆ A mechanism for detecting database changes in real time and relaying them to other systems.
CHECK Constraint RDBMS Fundamentals ☆ A constraint that guarantees a column's value satisfies a specified condition.
ClickHouse Major Products ☆ A column-oriented analytics database strong at aggregating large volumes of data.
Clustered Index Performance ☆ An indexing method that keeps the physical order of the stored data aligned with the index's own ordering.
CockroachDB Major Products ☆ A SQL-compatible distributed database strong at spreading across multiple locations.
Column-Oriented Database NoSQL ☆ A database that stores data by column, strong at aggregate processing.
Commit Transactions ☆ The operation that finalizes a transaction's changes.
Composite Index Performance ☆ An index built from a combination of multiple columns.
Composite Key RDBMS Fundamentals ☆ A primary key formed by combining multiple columns.
Connection Leak Performance ☆ A bug where an acquired database connection is not properly released, gradually exhausting the connection pool.
Connection Pool Performance ☆ A mechanism that pre-establishes multiple DB connections and reuses them.
Constraint RDBMS Fundamentals ☆ A rule set to keep data consistent.
COUNT Function SQL ☆ An aggregate function that counts rows.
Covering Index Performance ☆ An index containing every column a query needs, avoiding a read of the underlying table.
CTE SQL ☆ A common table expression usable within a query under a temporary name.
Data Lake Analytics Platforms ☆ A repository that stores raw data as-is, regardless of format.
Data Mart Analytics Platforms ☆ A small-scale data platform tailored to a specific department or use case.
Data Warehouse Analytics Platforms ☆ A mechanism for consolidating and accumulating large volumes of data for analysis.
DB2 Major Products ☆ A commercial RDBMS from IBM, also used on mainframes.
DDL (Data Definition Language) SQL ☆ A general term for the SQL statements that define or change the structure of a database itself, such as tables and indexes.
Deadlock Transactions ☆ A state where multiple processes wait on each other's locks and none can proceed.
DELETE Statement SQL ☆ A SQL statement for deleting data.
Denormalization RDBMS Fundamentals ☆ A design technique that deliberately combines normalized tables, tolerating duplicate data to avoid the need for joins.
Differential Backup Operations Management ☆ A backup method that captures only what changed since the most recent full backup.
Dimension Table Analytics Platforms ☆ A table holding attribute information, such as dates or product names, that serves as an angle for analysis.
Dirty Read Transactions ☆ A phenomenon where a transaction reads changes made by another transaction that hasn't been committed yet.
DISTINCT SQL ☆ A qualifier that retrieves results with duplicate rows removed.
Distributed Transaction Transactions ☆ A mechanism for treating an operation that spans multiple databases or services as a single atomic unit.
Document-Oriented Database NoSQL ☆ A kind of NoSQL database that stores data in a JSON-like structure.
DuckDB Major Products ☆ An embeddable, column-oriented database specialized for analytics.
Elasticsearch Major Products ☆ An engine for fast full-text search and analysis over large volumes of data.
ELT Analytics Platforms ☆ A data-integration approach that loads data first and transforms it inside the database.
ER Diagram RDBMS Fundamentals ☆ A diagram representing the relationships between tables.
ETL Analytics Platforms ☆ A pipeline that extracts, transforms, and loads data.
Eventual Consistency NoSQL ☆ A consistency model that tolerates a temporary gap until an update reaches every node.
Exclusive Lock Transactions ☆ A lock that prevents other processes from accessing something at the same time.
Execution Plan Performance ☆ A plan showing how SQL will be executed.
EXISTS Operator SQL ☆ An operator that checks only whether one or more rows exist in the result of a subquery.
Fact Table Analytics Platforms ☆ A table holding the numeric data being analyzed, such as sales or counts.
Foreign Key RDBMS Fundamentals ☆ A field that references another table's primary key, representing a relationship between tables.
Full Backup Operations Management ☆ A backup method that captures the entire database in one go.
FULL OUTER JOIN SQL ☆ A JOIN that keeps all rows from both tables, including the parts that don't match.
Full Scan Performance ☆ Scanning every row without using an index.
Full-Text Search Index Performance ☆ An index that treats words within text as searchable, enabling fast keyword search.
Graph Database NoSQL ☆ A database well suited to representing and querying connections between data.
Greenplum Major Products ☆ An open-source MPP analytics database built on top of PostgreSQL.
GROUP BY SQL ☆ A clause that groups data by specified fields.
Hash Index Performance ☆ An index specialized for exact-match lookups, using a value produced by running the search key through a hash function.
Hash Join Performance ☆ A JOIN execution method that builds a hash table from the join key and uses it to quickly find matching rows.
HAVING Clause SQL ☆ A clause that filters grouped results.
HBase Major Products ☆ A distributed, wide-column NoSQL database for large-scale data that runs on top of HDFS.
Hot Standby Operations Management ☆ A standby system kept running at all times, ready to switch over the moment there's a failure.
HTAP Analytics Platforms ☆ An approach that handles both transactional and analytical processing within a single database.
Idempotency Transactions ☆ The property where performing the same operation multiple times produces the same result as performing it once.
IN Operator SQL ☆ An operator that checks whether a value matches any item in a specified list.
Incremental Backup Operations Management ☆ A backup method that captures only what changed since the previous backup.
Index Performance ☆ A table-of-contents-like data structure created to speed up searches.
InfluxDB Major Products ☆ A database specialized for recording and analyzing time-series data.
INNER JOIN SQL ☆ A join method that combines only the data matching on both sides.
INSERT Statement SQL ☆ A SQL statement for adding new data.
Isolation Level Transactions ☆ The degree to which concurrent transactions can affect one another.
JOIN SQL ☆ An operation that associates and combines multiple tables.
Key-Value Store NoSQL ☆ A simple NoSQL store that saves data as key-value pairs.
Lakehouse Analytics Platforms ☆ A platform combining a data lake's flexibility with a data warehouse's management features.
LEFT JOIN SQL ☆ A JOIN based on the left table that fills unmatched rows with NULL.
LIKE Operator SQL ☆ An operator for searching strings by partial or prefix match, among others.
LIMIT Clause SQL ☆ A clause that limits the number of result rows returned.
MariaDB Major Products ☆ A highly compatible RDBMS developed as a fork of MySQL.
Master-Slave Configuration Operations Management ☆ A configuration that consolidates writes onto one node and propagates them to replicas.
Materialized View Analytics Platforms ☆ A view that stores a query's result as an actual copy, letting it be read back quickly.
Migration Operations Management ☆ Moving a schema or data to another environment or version.
Milvus Major Products ☆ An open-source vector database specialized for searching large-scale embedding vectors.
MongoDB Major Products ☆ A leading document-oriented NoSQL database that handles data in a JSON-like format.
MVCC Transactions ☆ A mechanism that shows readers a different version of data being updated, to reduce contention.
MySQL Major Products ☆ The most widely used open-source RDBMS in the world.
N+1 Problem Performance ☆ An inefficient state where a query that could be batched is instead issued repeatedly.
Neo4j Major Products ☆ A graph database specialized for handling connections between data.
Nested Loop Join Performance ☆ A JOIN execution method that, for each row in one table, scans through the other table looking for matching rows.
Non-Clustered Index Performance ☆ An indexing method that keeps a separate sort order and pointers to the data, independent of the data's physical storage order.
Non-Repeatable Read Transactions ☆ A phenomenon where reading the same row twice within one transaction returns different content because another transaction updated it in between.
Normalization RDBMS Fundamentals ☆ Organizing table structure to reduce data duplication and inconsistency.
NoSQL NoSQL ☆ An umbrella term for databases handling a variety of data models other than the relational one.
NOT NULL Constraint RDBMS Fundamentals ☆ A constraint that disallows NULL in a specified column.
OLAP Analytics Platforms ☆ A processing style for aggregating and analyzing data multidimensionally.
OLTP Analytics Platforms ☆ A processing style that handles a high volume of small data operations, such as day-to-day transactions.
Optimistic Locking Transactions ☆ A locking approach that checks for consistency only at update time, assuming conflicts are rare.
Oracle Database Major Products ☆ A leading commercial RDBMS widely used in the enterprise space.
ORDER BY SQL ☆ A clause that sorts results by a specified field.
OUTER JOIN SQL ☆ A join method that includes data even when it doesn't match.
Parquet Analytics Platforms ☆ An open, column-oriented data file format optimized for analytics.
Partition Key NoSQL ☆ The key that determines which node data is placed on.
Partition Pruning Performance ☆ An optimization that automatically excludes partitions from a search when a query's conditions show they can't contain relevant data.
Partitioning Performance ☆ Splitting one large table into multiple physical units for management.
Pessimistic Locking Transactions ☆ A locking approach that acquires a lock up front, assuming a conflict will occur.
Phantom Read Transactions ☆ A phenomenon where running the same query twice within one transaction returns a different number of rows because another transaction committed in between.
Pinecone Major Products ☆ A leading managed vector-database service, used in AI applications such as RAG.
Point-in-Time Recovery Operations Management ☆ A feature for restoring data to its state at any given point in time.
PostgreSQL Major Products ☆ A feature-rich, highly extensible open-source RDBMS.
Primary Key RDBMS Fundamentals ☆ A field for uniquely identifying a row within a table.
Qdrant Major Products ☆ An open-source vector database specialized for fast similarity search.
Query Optimizer Performance ☆ The internal database component that determines the most efficient way to actually execute a SQL statement and builds its execution plan.
Query Tuning Performance ☆ The work of improving how efficiently SQL executes.
Redis Major Products ☆ A fast key-value data store that handles data in memory.
Referential Integrity RDBMS Fundamentals ☆ A constraint that guarantees the data a foreign key points to always exists.
Relational Database RDBMS Fundamentals ☆ A database that manages data in tables and links them through relationships.
Replication NoSQL ☆ A mechanism that copies data to multiple locations to increase availability.
Replication Lag Operations Management ☆ The time gap between when the master and a replica reflect data.
Restore Operations Management ☆ Restoring data from a backup.
RIGHT JOIN SQL ☆ A JOIN based on the right table that fills unmatched rows with NULL.
RocksDB Major Products ☆ An embedded key-value store designed for high-performance reads and writes.
Rollback Transactions ☆ An operation that cancels a transaction and reverts to its pre-execution state.
Row Level Security RDBMS Fundamentals ☆ A feature that controls access to a table with fine-grained control down to the individual row.
Row-Level Locking Transactions ☆ A locking method that locks only the rows being updated, rather than the whole table.
Row-Oriented Database RDBMS Fundamentals ☆ The traditional database storage approach that stores data grouped together by row (record).
Savepoint Transactions ☆ A marker set partway through a transaction that lets you partially roll back to it.
Schema RDBMS Fundamentals ☆ A definition of a database's structure (tables and fields).
Schemaless NoSQL ☆ The property of being able to store data without defining a strict structure up front.
Schema-on-Read Analytics Platforms ☆ A design approach where the schema is applied at read time rather than at write time.
ScyllaDB Major Products ☆ A Cassandra-compatible database built to deliver higher performance.
Secondary Index NoSQL ☆ An additional index that enables efficient searching on columns other than the primary key.
SELECT Statement SQL ☆ A SQL statement for retrieving data from a database.
Sharding NoSQL ☆ A mechanism for distributing data across multiple servers.
Shared Lock Transactions ☆ A lock that allows multiple readers but restricts writing.
SingleStore Major Products ☆ A database for real-time analytics that handles both OLTP and OLAP in a single system.
Slow Query Log Performance ☆ A log that records queries that took a long time to execute.
Snapshot Isolation Transactions ☆ An isolation level that guarantees the view of data as it stood when a transaction began.
Snowflake Schema Analytics Platforms ☆ A design that further normalizes the dimension tables of a star schema.
Sort Key NoSQL ☆ A key that determines the order data is stored in within the same partition.
SQL Server Major Products ☆ A commercial RDBMS from Microsoft.
SQLite Major Products ☆ A lightweight RDBMS that requires no server and can be embedded in an app.
Star Schema Analytics Platforms ☆ A data design where a central fact table is surrounded by multiple dimension tables.
Stored Procedure RDBMS Fundamentals ☆ A sequence of logic registered ahead of time on the database side.
Subquery SQL ☆ A SQL statement embedded inside another SQL statement.
SUM Function SQL ☆ An aggregate function that sums a column's values.
Supabase Major Products ☆ An open-source Backend-as-a-Service (BaaS) built on PostgreSQL.
SurrealDB Major Products ☆ A multi-model database that handles relational, document, and graph data in one.
Table RDBMS Fundamentals ☆ A table made up of rows and columns that stores data.
TiDB Major Products ☆ A MySQL-compatible distributed database that scales horizontally with ease.
Time Travel Query Analytics Platforms ☆ A feature that lets you query a table's state as it existed at any point in the past.
TimescaleDB Major Products ☆ A time-series database implemented as a PostgreSQL extension.
Transaction Transactions ☆ A unit that treats multiple operations as one indivisible group.
Trigger RDBMS Fundamentals ☆ Logic that automatically runs in response to a specific operation.
Two-Phase Commit Transactions ☆ A procedure for keeping transactions consistent across multiple databases.
UNION SQL ☆ An operator that stacks multiple SELECT results together, removing duplicates.
Unique Constraint RDBMS Fundamentals ☆ A constraint that prevents a specified column's values from being duplicated within a table.
UPDATE Statement SQL ☆ A SQL statement for updating existing data.
UPSERT SQL ☆ An operation that updates a row if it already exists, or inserts it if it doesn't, all in a single statement.
Valkey Major Products ☆ A BSD-licensed fork that emerged in response to Redis's license change.
Vector Database NoSQL ☆ A database that stores embedding vectors and lets you search by semantic closeness. Widely used in RAG.
Vertica Major Products ☆ A column-oriented MPP database built specifically for large-scale analytics.
View RDBMS Fundamentals ☆ A virtual table that lets you treat a SELECT statement's result as if it were a table.
Weaviate Major Products ☆ An open-source vector database known for hybrid search that combines vector search with keyword search.
Window Function SQL ☆ A function that attaches a per-group aggregate value to each row without collapsing them.
YugabyteDB Major Products ☆ A distributed SQL database with a PostgreSQL-compatible API.
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