Is Ignite an in-memory database?
Yes. Even though Ignite memory-centric storage works well in-memory and on-disk, the disk persistence can be disabled and Ignite can act as a distributed in-memory database, with support for SQL and distributed joins.
Read more: In-Memory Database
Is Ignite an in-memory data grid?
Yes. Ignite is a full-featured distributed key-value data grid, which can be used either in memory-only mode or with Ignite native persistence. It can also automatically integrate with any 3rd party databases, including any RDBMS or NoSQL stores.
Read more: In-Memory Data Grid
Is Ignite a distributed cache?
Yes. When native persistence is disabled, Ignite becomes a distributed cache. Ignite implements JCache specification (JSR 107) and provides a lot more functionality than required by the specification, including partitioned and replicated distribution modes, distributed ACID transactions, SQL queries, native persistence, and more.
Read more: Database Caching
Is Ignite a distributed database?
Yes. Data in Ignite is either partitioned or replicated across a cluster of multiple nodes. This provides scalability and adds resiliency to the system. Ignite automatically controls how data is partitioned, however, users can plugin their own distribution (affinity) functions and collocate various pieces of data together for efficiency.
Read more: Distributed Database
Is Ignite an SQL database?
Not fully. Although Ignite aims to behave like any other relational SQL database, there are differences in how Ignite handles constraints and indexes. Ignite supports primary and secondary indexes, however, the uniqueness can only be enforced for the primary indexes. Ignite also does not support foreign key constraints.
Read more: SQL Database
Is Ignite a disk or memory-only storage?
Both. Native persistence in Ignite can be turned on and off. This allows Ignite to store data sets bigger than can fit in the available memory. Essentially, smaller operational data sets can be stored in-memory only, and larger data sets that do not fit in memory can be stored on disk, using memory as a caching layer for better performance.
Read more: Native Persistence
Is Ignite a NoSQL database?
Not exactly. Just like other NoSQL databases, Ignite is highly available and horizontally scalable. However, unlike other NoSQL databases, Ignite supports SQL and ACID transactions across multiple cluster nodes.
Read more: Ignite for NoSQL
Is Ignite a transactional database?
Not fully. ACID Transactions are supported, but only at key-value API level.
Ignite also supports cross-partition transactions, which means that transactions can span keys
residing in different partitions on different servers.
At SQL level Ignite supports atomic, but not yet transactional consistency. Ignite community plans to implement SQL transactions in version 2.5.
Read more: ACID Transactions
Is Ignite a multi-model database?
Yes. Ignite supports both, key-value and SQL for modelling and accessing data. In addition, Ignite provides strong processing APIs for computing on distributed data.
Read more: Distributed Database
Is Ignite a key-value store?
Yes. Ignite provides a feature rich key-value API, that is JCache (JSR-107) compliant
and supports Java, C++,
Read more: Key-Value Store
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