A hybrid network-based database system for handling OLTP and OLAP queries using decoupled compute and storage devices. A set of decoupled compute instances perform transactions on an OLTP database, and the data is replicated to an OLAP database, which is managed by another set of decoupled compute instances. Further, in response to queries, the database system can retrieve data from the OLTP and OLAP database for merging and processing according to the query.

Systems and methods for data access management can include one or more processors determining settings defining a workspace of a user responsive to a request to establish a session with the workspace, and identifying a set of data items of the workspace using the settings and one or more control access permissions of the user. The one or more processors can generate a database of the workspace using copies of the set of data items, and providing the user access to the database. The one or more processors may delete the database upon detecting closing of the workspace

A method, computer program product, and computer system for improving performance of a SQL execution sequence of SQL statements. The SQL execution sequence is recorded in an event log. Original results of executing the SQL statements and an original CPU cost of executing the SQL statements in accordance with the original access path are recorded in a logical log. A new access path is generated from analysis of the event log and the logical log. The SQL statements are executed in accordance with the new access path resulting in new results of executing the SQL statements including a new CPU cost of executing the SQL statements in accordance with the new access path. In response to a determination that the new results replicate the original results and that the new CPU cost is less than the original CPU cost, the original access path is replaced with the new access path.

Systems and methods are described for modifying input and output (I/O) to an object storage service by implementing one or more owner-specified functions to I/O requests. A function can implement a data manipulation, such as filtering out sensitive data before reading or writing the data. The functions can be applied prior to implementing a request method (e.g., GET or PUT) specified within the I/O request, such that the data to which the method is applied my not match the object specified within the request. For example, a user may request to obtain (e.g., GET) a data set. The data set may be passed to a function that filters sensitive data to the data set, and the GET request method may then be applied to the output of the function. In this manner, owners of objects on an object storage service are provided with greater control of objects stored or retrieved from the service.

Disclosed herein are system, method, and computer program product embodiments for providing read queries latch-free access to an index page. In an embodiment, a processor receives a request from a read query to access one or more records of an index page. The index page includes an update pointer and a slot array. The processor locates one or more updates prepended to the index page by locating a most recently prepended update indicated by the update pointer. Then, the processor generates a local offset table with entries in the slot array and the located one or more updates. The generated local offset table enables the processor to provide the read query access to the one or more records of the index page.

Methods for optimization in query plans are performed by computing systems via a query optimizer advisor. A query optimizer advisor (QO-Advisor) is configured to steer a query plan optimizer towards more efficient plan choices by providing rule hints to improve navigation of the search space for each query in formulation of its query plan. The QO-Advisor receives historical information of a distributed data processing system as an input, and then generates a set of rule hint pairs based on the historical information. The QO-Advisor provides the set of rule hint pairs to a query plan optimizer, which then optimizes a query plan of an incoming query through application of a rule hint pair in the set. This application is based at least on a characteristic of the incoming query matching a portion of the rule hint pair.

A query processing device is provided, including a processor coupled to a communication interface and a query storage. The processor receives a current submission of a query in a training mode, a stored prior execution plan, and stored statistics for the prior execution plan. The processor generates a current execution plan for the query, executes the current execution plan, and collects statistics. The processor stores the current execution plan and the statistics in the query storage and determines, based on the current execution plan, that the query is not in the training mode. The processor selects an execution plan for the query from among a plurality of stored execution plans for the query, including the prior execution plan and the current execution plan, and stores the selected execution plan for the query in the query storage with an indication that the query is not in the training mode.

A computer-implemented database access method includes receiving, by a server, a database access statement including a target identifying parameter; parsing the database access statement to determine the target identifying parameter; determining a statement type of the database access statement; obtaining a pre-stored execution plan group corresponding to the statement type, the pre-stored execution plan group including one or more execution plans for accessing a database corresponding to the database access statement, in which each execution plan corresponds to a different respective identifying parameter; selecting a target execution plan from the pre-stored execution plan group based on the target identifying parameter; and executing the target execution plan.

A method includes generating a table in a relational database, the table comprising an empty column reserved for a custom tag. The column has a default column name. The method also includes, in response to an instruction to create the custom tag, generating a column mapping that maps a name of the custom tag to the column name. The column mapping is stored outside the relational database and is used by a parser to translate between the name of the custom tag and the column name.

A method and system for code introspection in a multi-tenant architecture. The method includes receiving a query for code introspection from an entity, retrieving context for the entity that sent the query, retrieving raw code information based on the query, filtering the raw code information based on the context, and returning the filtered code information.