Abstract: Embodiments of the present disclosure may provide a dynamic query execution model. This query execution model may provide acceleration by scaling out parallel parts of a query (also referred to as a fragment) to additional computing resources, for example computing resources leased from a pool of computing resources. Execution of the parts of the query may be coordinated by a parent query coordinator, where the query originated, and a fragment query coordinator.

Abstract: A data platform that implements memoizable functions for database objects. The data platform detects a first execution of a memoizable function and generates a first key based on metadata of one or more database objects operated on by the memoizable function and generates a first result for the memoizable function based on the one or more database objects. The data platform detects a second execution of the memoizable function and generates a second key based on the metadata of the one or more database objects operated on by the memoizable function. When the first key and the second key are equal, the data platform reuses the first result of the memoizable function. When the first key and second key do not match, the data platform generates a second result for the second execution of the memoizable function.

Abstract: A source table can be provided by a provider account in a data system. A secure view of the source table is provided to one or more consumer accounts, the secure view limiting access to a subset of data in the source table. A plan to execute a command using the secure view may be generated, the plan including a secure view boundary on a subset of operations defining the secure view. The plan may be modified to move a first operation that was outside the secure view boundary to within the secure view boundary to generate a second plan to optimize performance in view of limitations or restrictions placed by the secure view.

Abstract: A hydrogenated styrenic block copolymer (HSBC) is disclosed represented by at least one formula selected from S-EP-EB, (S-EP-EB)nX, and S-EP-EB-EP-S, wherein n is from 2 to 30 and X is a residue of a coupling agent. Prior to hydrogenation, each block S is a polymer block of a vinyl aromatic monomer, each block EP is a polyisoprene block, and each block EB is a polybutadiene block. The HSBC has a polystyrene content (PSC) of 5 to 20 wt. %, and a peak molecular weight (Mp) of 45 to 300 kg/mol. A thermoplastic composition is disclosed containing the HSBC and a polyolefin. The thermoplastic composition shows improved impact performance and toughness.

Abstract: The subject technology receives a query, the query including a set of statements for performing the query. The subject technology populates a compilation context based at least in part the query. The subject technology invokes a compiler to perform a compilation process based on the compilation context. The subject technology performs a lookup operation on a stored plan cache for an exact match based on information from the compilation context. The subject technology, in response to determining an exact match, determines whether the particular query plan requires re-compilation based on a data dependent optimization. The subject technology determines whether a plan cache entry corresponding to the particular query plan includes a data property constraint. The subject technology determines whether the data property constraint still holds based on a set of data properties.

Abstract: A system to repeatedly execute a test run of a workload using resources of a cloud environment to determine whether there is a performance difference in the test run. The system to, in response to determining that there is no performance difference, identify one or more sets of decreased resources of the cloud environment. The system to re-execute the test run using the one or more sets of decreased resources of the cloud environment to determine whether there is a performance difference in the test run that is attributed to the one or more sets of decreased resources of the cloud environment. The system to determine minimum resources of the cloud environment to repeatedly execute the test run using the minimum resources without existence of a performance difference in response to re-executing the test run using the one or more sets of decreased resources of the cloud environment.

Abstract: The disclosure relates to a hydrogenated styrene-based multiblock copolymer composition, having selectively quaternized midblock, for forming anion-exchange membranes (AEMs). The quaternized hydrogenated styrene-based multiblock copolymer is characterized as having a high glass transition temperature from the hydrophobic end-blocks, low vinyl (rubber) content, and quaternized mid-block. AEMs made from the composition have improved thermal and dimensional stability in electrolyzer operations.

Abstract: The subject technology receives, during a query compilation process, a query directed to a set of source tables. The subject technology performs, during the query compilation process, a modification of the query for adjusting at least one pruning operation. The subject technology determines, during a pruning process of a second query, the second query directed to a set of files in a database system and including a set of pruning operations on the set of files, whether to perform a pruning cutoff on the set of pruning operations, the pruning process performing a depth first search of a pruner tree structure, the set of files comprising a set of micro-partitions. The subject technology performs the pruning cutoff based on the determining, the pruning cutoff ceasing at least one pruning operation from the set of pruning operations.

Abstract: Techniques for schema mismatch detection and evolution are described. When data is being uploaded into a source table, schema of the data to be uploaded can be compared with the schema for the source table. If a schema mismatch is detected, the schema of the source table can be modified, and the upload can be continued without data loss.

Abstract: Provided herein are systems and methods for automating the rollout of database changes. For example, a method includes detecting a change in database code of a database resulting in a changed database code. The change in the database code includes a parameter rollout for at least one parameter setting of the database. Execution of a query associated with the change in the database code is monitored. The query uses the at least one parameter setting. A regression in the changed database code is detected based on the monitoring. Impact analysis is performed to determine a scope of impact of the regression on at least another query using the at least one parameter setting. A determination is made on whether to perform a rollback of the change in the database code or perform mitigation based on the scope of impact.

Abstract: A composition is disclosed comprising a sulfonated styrenic block copolymer (SSBC) having an ion exchange capacity (IEC) of at least 0.5 meq/g; and at least one compound which reacts with the SSBC forming a cross-linked SSBC. The compound is selected from: (i) a cross-linking agent, (ii) a metal cation, and (iii) a non-sulfonated polymer. A film prepared from the composition containing the cross-linked SSBC has a toughness in wet state measured after 1 week of 1.2 to 8 MJ/m3; and a tensile stress in wet state measured after 1 week of 3.2 to 8 MPa, according to ASTM D412. The film can be used as a water 10 purification membrane or an antimicrobial protection layer.

Abstract: A method is provided for removing a residue from a surface. The method includes steps of applying a cleaning medium to the surface containing the residue. The cleaning medium comprises up to 100 wt. % of at least a solvent. Allowing the cleaning medium to be in contact with the residue for at least 5 seconds to swell/dissolve the residue for removing the residue from the surface. At least 50 wt. % of the residue and the cleaning medium are removed from the surface by wiping the surface with a shear force. The residue contains a sulfonated polymer having an ion exchange capacity (IEC) of greater than 0.5 meq/g. The sulfonated polymer can kill >90% of microbes coming in contact with the sulfonated polymer in less than 30 min.

Abstract: Embodiments of the present disclosure describe systems, methods, and computer program products for improving query processing of a database. An example method can include: storing table data for a table in a plurality of micro-partitions, each micro-partition comprising a portion of the table data for the table; for each micro-partition of the plurality of micro-partitions, storing metadata for the micro-partition in at least one of a plurality of expression properties; and selecting, by a processing device, a subset of the plurality of expression properties to be grouped into a grouping expression property based at least partially on the metadata of the subset of the plurality of the expression properties. The grouping expression property may include cumulative metadata associated with the metadata of the subset of the plurality of expression properties.

Abstract: Methods, systems, and computer programs are presented for providing a cluster view method of a database to perform compaction and clustering of database objects, such as database materialized view. A cluster view system identifies a materialized view including data from one or more base tables, a portion of the data of the materialized view including stale data. The cluster view system performs an integrated task within a maintenance operation on a database, the integrated task including compacting the materialized view, the maintenance operation including clustering the materialized view, and stores the compacted and clustered materialized view in the database.

Abstract: Joining data using a disjunctive operator is described. An example computer-implemented method can include generating, with a processing device, a query plan for a query, the query comprising a join operator expression for a disjunctive predicate, wherein the join operator expression includes a conjunctive predicate and a disjunctive operator. The method may further include generating a bloom filter for the disjunctive operator. Additionally, the method may include generating a result set as a result of evaluating the join operator expression using the disjunctive operator and bloom filter for the disjunctive predicate.

Abstract: Embodiments of the present disclosure may provide dynamic and fair assignment techniques for allocating resources on a demand basis. Assignment control may be separated into at least two components: a local component and a global component. Each component may have an active dialog with each other; the dialog may include two aspects: 1) a demand for computing resources, and 2) a total allowed number of computing resources. The global component may allocate resources from a pool of resources to different local components, and the local components in turn may assign their allocated resources to local competing requests. The allocation may also be throttled or limited at various levels.

Abstract: The subject technology receives a query, the query including a set of statements for performing the query. The subject technology populates a compilation context based at least in part the query. The subject technology invokes a compiler to perform a compilation process based on the compilation context. The subject technology performs a lookup operation on a stored plan cache for an exact match based on information from the compilation context. The subject technology, in response to determining an exact match, determines whether the particular query plan requires re-compilation based on a data dependent optimization. The subject technology determines whether a plan cache entry corresponding to the particular query plan includes a data property constraint. The subject technology determines whether the data property constraint still holds based on a set of data properties.

Abstract: Techniques for join elimination are described herein. Join elimination can identify and eliminate unnecessary joins in a query plan node. For example, join elimination can involve a semantic query optimization technique, which removes reference to a table whose columns are only referenced in join predicates if the joins do not filter/expand rows in the result. Such joins can cause significant performance issues on larger datasets if not optimized.

Abstract: Techniques for schema mismatch detection and evolution are described. When data is being uploaded into a source table, schema of the data to be uploaded can be compared with the schema for the source table. If a schema mismatch is detected, the schema of the source table can be modified, and the upload can be continued without data loss.