Abstract: A database system includes a persistent storage system, a memory storing metadata defining a tenant object and a plurality of database artifacts, a first instance of the tenant object, the first instance associated with a first plurality of the database artifacts including first data associated with the first instance of the tenant object, and a second instance of the tenant object, the second instance associated with a second plurality of the database artifacts including second data associated with the second instance of the tenant object. A processing unit is to execute program code of a database instance to cause the database system to encrypt the first data associated with the first instance of the tenant object using a first public encryption key and store the encrypted first data in the persistent storage system, and encrypt the second data associated with the second instance of the tenant object using a second public encryption key and store the encrypted second data in the persistent storage system.

Abstract: Systems and methods include creation of a first instance of a tenant object in a database instance, association of the first instance of the tenant object with a first plurality of database artifacts including first data associated with the first instance of the tenant object, creation of a second instance of the tenant object in the database instance, association of the second instance of the tenant object with a second plurality of database artifacts including second data associated with the second instance of the tenant object, and reception and response to queries on the first data associated with the first instance of the tenant object and to queries on the second data associated with the second instance of the tenant object.

Abstract: An in-memory database server hosting a tenant of a multi-tenant software architecture can receive a definition of a custom data field that is unique to an organization having isolated access to the tenant. The custom data field can extend a standard table defined by central metadata stored at a system tenant of the multi-tenant software architecture. Tenant private metadata that includes the definition can be stored in memory accessible only to the tenant. A tenant-dependent table that includes the custom data field can be formed, for example by retrieving central metadata defining the standard table from the system tenant and adding the custom data field using the definition. The tenant-dependent table can be presented for access via a database client at the organization. Related systems, articles of manufacture, and computer-implemented methods are disclosed.

Abstract: In some embodiments, a method determines a query distinction bit (D-bit) slice for a query key using values at D-bit positions that are associated with a node in the data structure. D-bit positions are determined based on branches in the data structure. The method selects a D-bit slice for a key in the set of keys for the node based on the D-bit slice of the query key and compares a key value for the key to a query key value for the query key to determine a first D-bit position value. A D-bit position that has a second D-bit position value that is smaller in value than the first D-bit position value is selected. The D-bit position is used to determine a result for the query key.

Abstract: An in-memory database server hosting a tenant of a multi-tenant software architecture can receive a definition of a custom data field that is unique to an organization having isolated access to the tenant. The custom data field can extend a standard table defined by central metadata stored at a system tenant of the multi-tenant software architecture. Tenant private metadata that includes the definition can be stored in memory accessible only to the tenant. A tenant-dependent table that includes the custom data field can be formed, for example by retrieving central metadata defining the standard table from the system tenant and adding the custom data field using the definition. The tenant-dependent table can be presented for access via a database client at the organization. Related systems, articles of manufacture, and computer-implemented methods are disclosed.

Abstract: An in-memory database server hosting a tenant of a multi-tenant software architecture can receive a definition of a custom data field that is unique to an organization having isolated access to the tenant. The custom data field can extend a standard table defined by central metadata stored at a system tenant of the multi-tenant software architecture. Tenant private metadata that includes the definition can be stored in memory accessible only to the tenant. A tenant-dependent table that includes the custom data field can be formed, for example by retrieving central metadata defining the standard table from the system tenant and adding the custom data field using the definition. The tenant-dependent table can be presented for access via a database client at the organization. Related systems, articles of manufacture, and computer-implemented methods are disclosed.

Abstract: Methods, systems, and computer-readable storage media for receiving a first storage request indicating a first type of data and a first size, identifying a first sub-space based on the first type, the first sub-space including a dense group of dense segments and a sparse group of sparse segments, and determining that the dense group of the first sub-space is absent a dense segment to store data of the first storage request based on the first size, and in response: determining whether the sparse group of the first sub-space includes a sparse segment to store the data of the first storage request based on the first size, and storing the data of the first storage request to the sparse group of the first sub-space in response to determining that the sparse group of the first sub-space includes a sparse segment to store the data of the first storage request.

Abstract: Methods, systems, and computer-readable storage media for determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space, in response to the first version, providing a version table for the page, the version table including a set of cells each cell corresponding to a record in the page, setting a version table pointer of the page to point to the version table, and setting a version pointer of a first cell to point to the first version in the version space, the first cell corresponding to a record of the data in the page.

Abstract: The disclosure relates a display apparatus comprising: a signal input receiver receives a plurality of signals which are different in kind from each other, a plurality of encoders provided respectively corresponding to the plurality of signals, and perform encoding of a corresponding mode according to the kinds of at least one signal input to the signal input receiver among the plurality of signals, a first interface transmits a signal obtained by serializing the encoded signal, a second interface deserializes the signal received from the first interface, a plurality of decoders provided respectively corresponding to the plurality of encoders, and perform decoding and restoring the deserialized signal into the at least one signal, and a display displays an image based on the at least one restored signal.

Abstract: A physio-logical migration of a database from a source system to a target system may include exporting a catalog of the database in a data interchange format that preserves the hierarchical dependencies present amongst the entities included in the catalog. The physio-logical migration of the database may further include exporting the contents of a table in the database in a binary format compatible at the target system. The binary format may be a data buffer having a metadata portion, a fixed-size portion, and a page chain portion. Where the target system is a cloud-based system, the physio-logical migration of the database may include exporting the catalog and the contents of the table to a cloud-based object store before importing the catalog and the contents of the table to the target system. Related systems and articles of manufacture, including computer program products, are also provided.

Abstract: Methods, systems, and computer-readable storage media for online defragmentation of memory in database systems by applying an IX-lock to each table having data stored in a marked page in a set of marked pages, generating a record map including key-value pairs, each being associated with a record location in a marked page, a value of each key-value pair initially set to a first value, iteratively executing the online defragmentation to delete data from marked pages and add the data to non-sparse pages, at least one iteration including applying a try-lock to a record in a marked page, and at iterations of the online defragmentation, updating the record map to change the value of at least one key-value pair from the first value to the second value, the second value representing that data of a marked page has been deleted from the marked page and added to a non-sparse page.

Abstract: Methods, systems, and computer-readable storage media for receiving a first storage request indicating a first type of data and a first size, identifying a first sub-space based on the first type, the first sub-space including a dense group of dense segments and a sparse group of sparse segments, and determining that the dense group of the first sub-space is absent a dense segment to store data of the first storage request based on the first size, and in response: determining whether the sparse group of the first sub-space includes a sparse segment to store the data of the first storage request based on the first size, and storing the data of the first storage request to the sparse group of the first sub-space in response to determining that the sparse group of the first sub-space includes a sparse segment to store the data of the first storage request.

Abstract: Technologies are described for restarting an application while maintaining data in memory (e.g., using shared memory). For example, shared memory can be associated with an application. The shared memory can also be associated with a holder process to maintain the shared memory from the time the application stops to the time the application starts again. When the application starts, the shared memory can be associated with the started application. In addition, restart of in-memory databases can be provided using shared memory. For example, in-memory data can be maintained when a database process or database management system stops and starts (e.g., during a restart).

Abstract: Methods, systems, and computer-readable storage media for determining that a first transaction results in a first version of data stored in a page in a database system, the first version being stored in a version space and the data being stored in a table space, in response to the first version, providing a version table for the page, the version table including a set of cells each cell corresponding to a record in the page, setting a version table pointer of the page to point to the version table, and setting a version pointer of a first cell to point to the first version in the version space, the first cell corresponding to a record of the data in the page.

Abstract: Methods, systems, and computer-readable storage media for online defragmentation of memory in database systems by applying an IX-lock to each table having data stored in a marked page in a set of marked pages, generating a record map including key-value pairs, each being associated with a record location in a marked page, a value of each key-value pair initially set to a first value, iteratively executing the online defragmentation to delete data from marked pages and add the data to non-sparse pages, at least one iteration including applying a try-lock to a record in a marked page, and at iterations of the online defragmentation, updating the record map to change the value of at least one key-value pair from the first value to the second value, the second value representing that data of a marked page has been deleted from the marked page and added to a non-sparse page.

Abstract: An in-memory database server hosting a tenant of a multi-tenant software architecture can receive a definition of a custom data field that is unique to an organization having isolated access to the tenant. The custom data field can extend a standard table defined by central metadata stored at a system tenant of the multi-tenant software architecture. Tenant private metadata that includes the definition can be stored in memory accessible only to the tenant. A tenant-dependent table that includes the custom data field can be formed, for example by retrieving central metadata defining the standard table from the system tenant and adding the custom data field using the definition. The tenant-dependent table can be presented for access via a database client at the organization. Related systems, articles of manufacture, and computer-implemented methods are disclosed.

Abstract: A system includes initiation of recovery from a crash of a database instance and, during the recovery, identification of a subset of pages of a memory image of the database instance which are not reusable and replacement of the identified subset of pages with corresponding pages of the savepoint image.

Abstract: A system includes initiation of recovery from a crash of a database instance and, during the recovery, identification of a subset of pages of a memory image of the database instance which are not reusable and replacement of the identified subset of pages with corresponding pages of the savepoint image.

Abstract: An in-memory database server hosting a tenant of a multi-tenant software architecture can receive a definition of a custom data field that is unique to an organization having isolated access to the tenant. The custom data field can extend a standard table defined by central metadata stored at a system tenant of the multi-tenant software architecture. Tenant private metadata that includes the definition can be stored in memory accessible only to the tenant. A tenant-dependent table that includes the custom data field can be formed, for example by retrieving central metadata defining the standard table from the system tenant and adding the custom data field using the definition. The tenant-dependent table can be presented for access via a database client at the organization. Related systems, articles of manufacture, and computer-implemented methods are disclosed.

Abstract: Restoring a database image of a secondary database system comprises initializing the database image from a recovery image that includes metadata logs and non-metadata logs, of which at least one metadata log includes an undo log of non-committed data that is applied to the initialized database image. A first pagelist and first indexes are then rebuilt based on first data segments of the database image and the corresponding metadata objects. The database image is then updated by replaying the metadata redo log generated from the undo log, the metadata logs, and the non-metadata logs. Then, a second pagelist and second indexes for the database system are rebuilt based on second data segments of the database image and the corresponding non-metadata objects, while each of the first data segments is statically separated from the second data segments in physical memory space. Related apparatus, systems, techniques and articles are also described.