Abstract: In accordance with an embodiment, described herein are systems and methods for providing direct access to a sharded database. A shard director provides access by software client applications to database shards. A connection pool (e.g., a Universal Connection Pool, UCP) and database driver (e.g., a Java Database Connectivity, JDBC, component) can be configured to allow a client application to provide a shard key, either during connection checkout or at a later time; recognize shard keys specified by the client application; and enable connection by the client application to a particular shard or chunk. The approach enables efficient re-use of connection resources, and faster access to appropriate shards.

Abstract: Techniques are provided for processing a database command in a sharded database. The processing of the database command may include generating or otherwise accessing a shard key expression, and evaluating the shard key expression to identify one or more target shards that contain data used to execute the database command.

Abstract: In accordance with an embodiment, the system enables access to a sharded database using a cache and a shard topology. A shard-aware client application connecting to a sharded database can use a connection pool (e.g., a Universal Connection Pool, UCP), to store or access connections to different shards or chunks of the sharded database within a shared pool. As new connections are created, a shard topology layer can be built at the database driver layer, which learns and caches shard key ranges to locations of shards. The shard topology layer enables subsequent connection requests from a client application to use a fast key path access to the appropriate shard or chunk.

Abstract: Described is a system, method, and computer program product is provided that implements high-volume data ingestion in a relational database system. A middle-tier structure is provided that sits between the IoT data producers and the back-end database system. Data records are gathered together and organized at the middle tier, and groups of those records are ingested on a group-basis into the database in a manner which bypasses standard SQL engine processing.

Abstract: Described herein are systems and methods for providing access to a database in a multi-tenant environment, including the use of a connection pool, and support for server-side connection pool multiple tagging. For example, the system can provide a capability to associate multiple connection properties with a particular server-side connection in, e.g., an Oracle Database Resident Connection Pooling (DRCP) environment; look up a connection with one or multiple properties; and provide information about a returned connection so that a requesting application can review the properties associated with the returned connection, in order to determine how best to “fix-up” or otherwise use that connection.

Abstract: Techniques are provided for processing a database command in a sharded database. The processing of the database command may include generating or otherwise accessing a shard key expression, and evaluating the shard key expression to identify one or more target shards that contain data used to execute the database command.

Abstract: In accordance with an embodiment, a system enables multidimensional search within a resource pool, to support complex borrow operations such as, for example, specifying ranges for particular connection properties. As threads access the pool, attempting to borrow connections having particular connection properties, one or more skipped pool elements can be represented as skip lists within a k-dimensional tree (KD-tree) or other data structure that enables searching across multiple dimensions. In response to receiving a request to borrow a connection having particular connection properties, a multidimensional search can be performed within the KD-tree to determine the availability of a connection having the requested properties.

Abstract: Techniques are provided for creating, organizing, and maintaining a sharded database. A sharded database can be created using user-defined sharding, system-managed sharding, or composite sharding. The sharded database is implemented with relational database techniques. The techniques described can be used to route database requests and process queries in a sharded database.

Abstract: In accordance with an embodiment, described herein is a system and method for connection concentration in a database environment. A transparency engine provided between client applications and a database can include a connection pool (e.g., UCP connection pool). The transparency engine can operate as a proxy engine for the database and as a session abstraction layer for the client applications, to enable the client applications to utilize features provided by the connection pool without code changes. The transparency engine can receive application connections from the client applications, and concentrate the application connections on a smaller number of database connections maintained in the connection pool.

Abstract: Techniques are provided for processing a database command in a sharded database. The processing of the database command may include generating or otherwise accessing a shard key expression, and evaluating the shard key expression to identify one or more target shards that contain data used to execute the database command.

Abstract: Described herein are systems and methods for providing access to a database in a multi-tenant environment, including the use of a connection pool, with support for efficient repurposing of connections. In accordance with an embodiment, a software application can request that a connection be provided, to enable access to the database. In response to receiving the request, the connection pool can first determine if a particular connection with the exact desired attributes already exists within the pool, but is borrowed at the time of the request. If such a connection exists, then the connection pool can wait a period of time for that particular connection to become available, referred to herein as a double-wait. Subsequently, if the particular connection is not made available within the double-wait time period, the connection pool resumes its usual operation, for example by repurposing other connections.

Abstract: In accordance with an embodiment, described herein is a system and method for connection concentration in a database environment. A transparency engine provided between client applications and a database can include a connection pool (e.g., UCP connection pool). The transparency engine can operate as a proxy engine for the database and as a session abstraction layer for the client applications, to enable the client applications to utilize features provided by the connection pool without code changes. The transparency engine can receive application connections from the client applications, and concentrate the application connections on a smaller number of database connections maintained in the connection pool.

Abstract: Techniques are provided for processing a database command in a sharded database. The processing of the database command may include generating or otherwise accessing a shard key expression, and evaluating the shard key expression to identify one or more target shards that contain data used to execute the database command.

Abstract: Techniques are described for closing one or more connections with a database management system (DBMS) as part of a planned operation such as maintenance and load balancing. In an embodiment, a request is received for a planned operation of a database server of a DBMS that requires releasing and migrating database sessions. Over a database connection with the database server, the DBMS or a Client-Driver on the client system that interfaces with the DBMS, may receive request(s) from the client system. Based on the request(s), a safe point, for the database connection with the database server, at which the database connection of the client system with the database server can be closed without affecting the success of execution of next one or more command that the client system intended to request the DBMS to execute on the database server, is determined.

Abstract: In accordance with an embodiment, described herein is a system and method for row buffering in a database environment. A transparency engine can be provided between client applications and a database, and can operate as a proxy engine for the database and as a session abstraction layer for the client applications, to enable the client applications to utilize database features provided by the connection pool without code changes to the client applications. The transparency engine can maintain a plurality of local row buffers to store rows fetched from a database. The local buffers can be filled by rows pre-fetched from the database. When a client application requests rows from the database, the transparency engine can first check whether the rows exist in a local buffer. If the rows are present in the local buffer, the transparency engine sends the rows to the requesting client application, without going to the database.

Abstract: In accordance with an embodiment, a system enables multidimensional search within a resource pool, to support complex borrow operations such as, for example, specifying ranges for particular connection properties. As threads access the pool, attempting to borrow connections having particular connection properties, one or more skipped pool elements can be represented as skip lists within a k-dimensional tree (KD-tree) or other data structure that enables searching across multiple dimensions. In response to receiving a request to borrow a connection having particular connection properties, a multidimensional search can be performed within the KD-tree to determine the availability of a connection having the requested properties.

Abstract: Described herein are systems and methods for providing access to a database in a multi-tenant environment, including the use of a connection pool, and support for limiting the maximum number of connections per tenant or per database shard. For example, when a tenant is associated with a service, configuring a maximum connections per service limit on a shared connection pool indicates to the system that the shared pool should not repurpose existing connections, or create new connections for a service, if the maximum connections per service limit has been reached for that particular service. The system can also maintain a parameter that keeps track of the total number of connections created to each shard of a sharded database. The connection pool can scan the sharded database topology, to determine which shard or sharded instance can satisfy the request, without exceeding the maximum limit for that shard.

Abstract: In accordance with an embodiment, described herein is a system and method for high availability and load balancing in a database environment. A transparency engine can be provided between client applications and a database, and can operate as a proxy engine for the database and as a session abstraction layer for the client applications, to enable the client applications to utilize database features provided by the connection pool without code changes to the client applications. The transparency can keep track of session states, request boundaries and cursors to efficiently reuse the database connections across the client applications. The transparency engine can use the request boundaries and indicators from the database to detect safe places to drain database connections in the event of database outages.

Abstract: Described herein are systems and methods for providing access to a database in a multi-tenant environment, including the use of a connection pool, and support for efficient connection validation. For example, the system can support a “seconds to trust idle connection” functionality, which enables lazy validation of connections in the connection pool. The seconds to trust idle connection is the time period, expressed, for example, as a number of seconds, within a particular connection usage, that the connection pool trusts that the connection is still viable, and if so will skip a connection validation test before delivering the connection to a requesting application.

Abstract: In accordance with an embodiment, a system enables multidimensional search within a resource pool, to support complex borrow operations such as, for example, specifying ranges for particular connection properties. As threads access the pool, attempting to borrow connections having particular connection properties, one or more skipped pool elements can be represented as skip lists within a k-dimensional tree (KD-tree) or other data structure that enables searching across multiple dimensions. In response to receiving a request to borrow a connection having particular connection properties, a multidimensional search can be performed within the KD-tree to determine the availability of a connection having the requested properties.