Abstract: A method for providing elastic columnar cache includes receiving cache configuration information indicating a maximum size and an incremental size for a cache associated with a user. The cache is configured to store a portion of a table in a row-major format. The method includes caching, in a column-major format, a subset of the plurality of columns of the table in the cache and receiving a plurality of data requests requesting access to the table and associated with a corresponding access pattern requiring access to one or more of the columns. While executing one or more workloads, the method includes, for each column of the table, determining an access frequency indicating a number of times the corresponding column is accessed over a predetermined time period and dynamically adjusting the subset of columns based on the access patterns, the maximum size, and the incremental size.

Abstract: A method, a system, and a computer program product for generating a query executable plan. A query requiring access to data stored in a database system is received. Based on the received query, a query execution plan having a plurality of query execution pipelines is generated. Each query execution pipeline in the plurality of query execution pipelines is configured to execute a plurality of operations in a predetermined order associated with each query execution pipeline. The generated query execution plan is fragmented into a plurality of fragments. Each fragment has one or more query execution pipelines in the plurality of query execution pipelines. The received query is executed by executing each fragment in the plurality of fragments.

Abstract: A system and method for processing a database query is described. In response to detection that a database query involves a star or snowflake join operation, a join operator in a preliminary query plan can be split into a build operator and a probe operator. The probe operator can be placed in a final query plan in the same place as the join operator in the preliminary query plan, while the build operator can be placed beneath the probe operator in the final query plan, between an exchange operator and the exchange operator's child from the preliminary query plan.

Abstract: Disclosed herein are system, method, and computer program product embodiments for generating a native access plan for semi join operators. An embodiment operates by generating a plurality of variables based upon the positions of a plurality of operators in a compiled query plan, opening and traversing tables as the query plan is executed, and closing those tables based on the rows queried and the plurality of variables.

Abstract: Disclosed herein are system, method, and computer program product embodiments for generating a native access plan from a query execution plan for dynamic entity calling. An embodiment operates by receiving the query execution plan comprising at least one call to an entity, the entity being implemented by a plurality of classes, and generating source code of a native access plan that implements the query execution plan. The source code of the native access plan includes instructions to translate a run-time call to the entity to a call to a corresponding implementation of the entity based on an identifier of the called implementation of the entity.

Abstract: Disclosed herein are system, method, and computer program product embodiments for eliminating redundancy when generating intermediate representation code. An embodiment operates by traversing a query execution plan, and for at least one operator in the query execution plan, determining whether the operator is derived from a parent class operator. If it is determined that the operator is derived from the parent class operator, source code for the native access plan is generated using one or more code generator functions corresponding to the parent class operator and/or one or more generator functions specifically corresponding to the child class operator. If it is determined that the operator is not derived from the parent class operator, source code for the native access plan is generated using one or more code generator functions corresponding to the operator.

Abstract: Disclosed herein are system, method, and computer program product embodiments for performing dynamic partition pruning using data statistic objects as data integrity constraints. An embodiment operates by partitioning a database table into a plurality of partitions based on a partition criterion. The embodiment creates a data statistics object for a partition in the plurality of partitions. The embodiment receives a query for the database table. The embodiment determines the data statistics object is consistent with data in the partition. The embodiment processes the query for the partition based on the data statistics object.

Abstract: Disclosed herein are system, method, and computer program product embodiments for determining a constraint data statistics object is consistent. An embodiment operates by receiving a query for a database table. The embodiment determines a constraint data statistic object associated with a partition of the database table. The embodiment determines the constraint data statistics object is consistent with a data state of the partition of the database table based on consistency metadata of the constraint data statistics object. The embodiment processes the query for the database table based on the determining the constraint data statistics object is consistent with the data state of the partition of the database table.

Abstract: A system and method for processing a database query is described. In response to detection that a database query involves a star or snowflake join operation, a join operator in a preliminary query plan can be split into a build operator and a probe operator. The probe operator can be placed in a final query plan in the same place as the join operator in the preliminary query plan, while the build operator can be placed beneath the probe operator in the final query plan, between an exchange operator and the exchange operator's child from the preliminary query plan.

Abstract: A system and method for processing a database query is described. The method can, in response to detection that a database query involves a star or snowflake join operation, determine a selectivity ratio for each of a plurality of dimension tables. The selectivity ratio having a lower value can correspond to a more restrictive dimension table. Thereafter, a table ordering can be created beginning with a fact table and continuing with each of the dimension tables in ascending order of their corresponding selectivity ratios. Then a query plan involving join operations between successive tables in the table ordering can be created.

Abstract: A system and method for processing a database query is described. In response to detection that a database query involves a star or snowflake join operation, a join operator in a preliminary query plan can be split into a build operator and a probe operator. The probe operator can be placed in a final query plan in the same place as the join operator in the preliminary query plan, while the build operator can be placed beneath the probe operator in the final query plan, between an exchange operator and the exchange operator's child from the preliminary query plan.

Abstract: Various embodiments of systems and methods to generate native access plan source code are described herein. In one aspect, a database query is received. A query execution plan, including a parent operator and one or more descendent operators, corresponding to the database query is retrieved. Further, a check is made to determine whether the parent operator and the one or more descendent operators include at least one loop. When both the parent operator and the one or more descendent operators include at least one loop, consume points for the at least one loop are defined. The parent operator and the one or more descendent operators are merged based on consume point types to generate native access plan source code.

Abstract: A method, a system and a computer program product for maintaining a pre-computed result set are disclosed. A server coupled to a data source determines whether an object stored in the data source received an update. The server identifies at least one identifier associated with a pre-computed result set based on that determination. The pre-computed result set is computed based on the object. The server computes an updated pre-computed result set using the identifier by applying the received update to the pre-computed result set.

Abstract: Disclosed herein are system, method, and computer program product embodiments for eliminating redundancy when generating intermediate representation code. An embodiment operates by traversing a query execution plan, and for at least one operator in the query execution plan, determining whether the operator is derived from a parent class operator. If it is determined that the operator is derived from the parent class operator, source code for the native access plan is generated using one or more code generator functions corresponding to the parent class operator and/or one or more generator functions specifically corresponding to the child class operator. If it is determined that the operator is not derived from the parent class operator, source code for the native access plan is generated using one or more code generator functions corresponding to the operator.

Abstract: Disclosed herein are system, method, and computer program product embodiments for generating a native access plan from a query execution plan for dynamic entity calling. An embodiment operates by receiving the query execution plan comprising at least one call to an entity, the entity being implemented by a plurality of classes, and generating source code of a native access plan that implements the query execution plan. The source code of the native access plan includes instructions to translate a run-time call to the entity to a call to a corresponding implementation of the entity based on an identifier of the called implementation of the entity.

Abstract: Disclosed herein are system, method, and computer program product embodiments for generating a native access plan for semi join operators. An embodiment operates by generating a plurality of variables based upon the positions of a plurality of operators in a compiled query plan, opening and traversing tables as the query plan is executed, and closing those tables based on the rows queried and the plurality of variables.

Abstract: An original query execution plan of a database query is received. The original query execution plan represents a tree of operators. Source code for the original query execution plan is generated by a single traversal of the tree of operators. The generated source code is compiled into native machine code. The native machine code represents a simplified native access plan (SNAP).

Abstract: Various embodiments of systems and methods to generate native access plan source code are described herein. In one aspect, a database query is received. A query execution plan, including a parent operator and one or more descendent operators, corresponding to the database query is retrieved. Further, a check is made to determine whether the parent operator and the one or more descendent operators include at least one loop. When both the parent operator and the one or more descendent operators include at least one loop, consume points for the at least one loop are defined. The parent operator and the one or more descendent operators are merged based on consume point types to generate native access plan source code.

Abstract: Bloom filter cost estimation engine for improved performance and accuracy is described. An example method includes building an execution plan for a join operation having a plurality of levels, where the execution plan includes a top join operator at a top level, a leaf scan operator on a bottom level, and one or more intermediate operators between the top level and the bottom level. A row reduction effect of applying a Bloom filter is determined by simulating a semi-join operation over table statistic representation at each of the plurality of levels of the execution plan. A cost savings of the join operation is calculated based on the row reduction effect at the each of the plurality of the levels.

Abstract: System and methodology for automatic tuning of database query optimizer is described.