Abstract: A computer-implemented method for a partitioned bloom filter merge is provided. A non-limiting example of the computer-implemented method includes partitioning, by a processing device, a bloom filter into N equal size filter partitions. The method further includes distributing, by the processing device, each of the filter partitions to an associated node. The method further includes merging, by the processing device, the filter partitions in each of the associated nodes. The method further includes redistributing, by the processing device, the merged filter partitions to each of the N nodes. The method further includes joining, by the processing device, the merged filter partitions in each of the N nodes to assemble a complete merged bloom filter.

Abstract: A computer-implemented method for a partitioned bloom filter merge is provided. A non-limiting example of the computer-implemented method includes partitioning, by a processing device, a bloom filter into N equal size filter partitions. The method further includes distributing, by the processing device, each of the filter partitions to an associated node. The method further includes merging, by the processing device, the filter partitions in each of the associated nodes. The method further includes redistributing, by the processing device, the merged filter partitions to each of the N nodes. The method further includes joining, by the processing device, the merged filter partitions in each of the N nodes to assemble a complete merged bloom filter.

Abstract: A computer-implemented method for a partitioned bloom filter merge is provided. A non-limiting example of the computer-implemented method includes partitioning, by a processing device, a bloom filter into N equal size filter partitions. The method further includes distributing, by the processing device, each of the filter partitions to an associated node. The method further includes merging, by the processing device, the filter partitions in each of the associated nodes. The method further includes redistributing, by the processing device, the merged filter partitions to each of the N nodes. The method further includes joining, by the processing device, the merged filter partitions in each of the N nodes to assemble a complete merged bloom filter.

Abstract: Conventionally, in addition to indexing, a synopsis of a base table of a database is used to skip and compress data. However, scanning of the entire synopsis for all queries is required, which takes a long time when the synopsis gets significantly big in a large data warehouse. A method for efficient data skipping and compression through vertical partitioning of data is provided to eliminate the cost of synopsis storage overhead while enabling the synopsis search functionality.

Abstract: A computer-implemented method for a partitioned bloom filter merge is provided. A non-limiting example of the computer-implemented method includes partitioning, by a processing device, a bloom filter into N equal size filter partitions. The method further includes distributing, by the processing device, each of the filter partitions to an associated node. The method further includes merging, by the processing device, the filter partitions in each of the associated nodes. The method further includes redistributing, by the processing device, the merged filter partitions to each of the N nodes. The method further includes joining, by the processing device, the merged filter partitions in each of the N nodes to assemble a complete merged bloom filter.

Abstract: Organizing data within a database is provided. In response to determining that a group of coarsified data records within a database table is not an aligned group of data records, a virtually replicated subgroup of coarsified data records that corresponds to the group of coarsified data records is generated from different groups of coarsified data records within the database table. The virtually replicated subgroup of coarsified data records is aligned with the corresponding group of coarsified data records.

Abstract: Conventionally, in addition to indexing, a synopsis of a base table of a database is used to skip and compress data. However, scanning of the entire synopsis for all queries is required, which takes a long time when the synopsis gets significantly big in a large data warehouse. A method for efficient data skipping and compression through vertical partitioning of data is provided to eliminate the cost of synopsis storage overhead while enabling the synopsis search functionality.

Abstract: An ordering of operations in log records includes: performing update operations on a database object by a node; writing log records for the update operations into a local buffer by the node, the log records each including a local virtual timestamp; determining that a log flush to write the log records in the local buffer to a persistent storage is to be performed; in response, sending a request from the node to a log flush sequence server for a log flush sequence number; receiving the log flush sequence number by the node; inserting the log flush sequence number into the log records in the local buffer; and performing the log flush to write the log records in the local buffer to the persistent storage, where the log records written to the persistent storage comprises the local virtual timestamps and the log flush sequence number.

Abstract: Organizing data within a database is provided. In response to determining that a group of coarsified data records within a database table is not an aligned group of data records, a virtually replicated subgroup of coarsified data records that corresponds to the group of coarsified data records is generated from different groups of coarsified data records within the database table. The virtually replicated subgroup of coarsified data records is aligned with the corresponding group of coarsified data records.

Abstract: A method, information processing system, and computer program storage product to compress sorted values. At least a first prefix and a second prefix in a plurality of prefixes are compared. Each prefix comprises at least a portion of a plurality of sorted values. A respective prefix comprises a set of consecutive characters including at least a first character of a respective sorted value. The respective sorted value further comprising a respective suffix comprising consecutive characters of the respective sorted value that are after the respective prefix. At least a respective first character of the first prefix and a respective first character of the second prefix are determined to be substantially identical. The first prefix is merged with the second prefix into a single prefix comprising the first character. A set of suffixes associated with the first prefix is updated to reflect an association with the second prefix.

Abstract: An index scan processor and method to perform concurrent scans of stored indexed data. An indexed data scanner performs a first scan of stored data by sequentially scanning through an index data structure and maintains, over a duration of the first scan, a first scan current scan location within the index data structure that indicates a currently accessed record within the stored data structure for the first scan. A scan manager accepts a request for a second scan of the stored data, determines, during the performing the first scan, a starting index scan location within the index data structure for the second scan that is sufficiently near the first scan current index scan location to cause records indicated by the starting location index to be stored within a buffer due to the performing the first scan, and starts the second scan at the starting location and proceeding to the second end key.

Abstract: Disclosed are a method, information processing system, and computer readable medium for managing table scan processes. The method includes monitoring a plurality of storage medium table scan processes. Each storage medium table scan process in the plurality of storage medium table scan processes is placed into a plurality of scan groups based on storage medium pages to be scanned by each of the storage medium table scan processes. Each storage medium table scan process in a scan group can share data within a storage medium page.

Abstract: An ordering of operations in log records includes: performing update operations on a shared database object by a node; writing log records for the update operations into a local buffer by the node, the log records each including a local virtual timestamp; determining that a log flush to write the log records in the local buffer to a persistent storage is to be performed; in response, sending a request from the node to a log flush sequence server for a log flush sequence number; receiving the log flush sequence number by the node; inserting the log flush sequence number into the log records in the local buffer; and performing the log flush to write the log records in the local buffer to the persistent storage, where the log records written to the persistent storage comprises the local virtual timestamps and the log flush sequence number.

Abstract: Disclosed are a method, information processing system, and computer readable medium for scanning a storage medium table. The method includes retrieving location information associated with at least one other storage medium table scan. A storage medium table scan is started at a location within a storage medium table based on at least a location of the one other storage medium table scan. A weight is assigned to at least one storage medium block based on at least a current scanning location within the storage medium table relative to the location of the one other table scan. The method determines if a distance between the current scanning location and the location of the one other table scan is greater than a first given threshold. A current scanning operation is delayed, in response to the distance being greater than the given threshold, until the distance is below a second given threshold.

Abstract: A method and processor to determine distances between multiple index driven scan operations. A first anchor index entry is identified during a first index scan and stored. A first number of index entries between the first anchor index entry and a first index scan location being processed by a first index scan is determined based on information maintained external to an index structure. A determination is made of second number of index entries between the first anchor index entry and a second index scan location being processed by a second index scan executing concurrently with the first index scan based on information maintained external to the index structure. A distance between the first index scan location and the second index scan location is calculated as equal to a difference between the first number of index entries and the second number of index entries.

Abstract: An information retrieval system and method are provided for minimizing the number of blocks searched in a cell before recording a new record in the table and determining which block can be assigned if a table has space available to store a new record in the case an additional block should be associated with a cell. Dimensions for a table are identified, and at least one block in the table is associated with a dimension value for each dimension, where each block comprises contiguous storage pages. The block can be further associated with a cell; this associated cell has a unique combination of dimension values comprising an dimension value for each of the dimensions. A unique associated bit list for each dimension value for each dimension has a unique corresponding list entry for each block associated with that dimension value, and a unique associated bit list for each cell has a unique corresponding list entry for each block associated with that cell.

Abstract: A method, information processing system, and computer program storage product for compressing sorted values is disclosed. At least a first prefix and a second prefix in a plurality of prefixes are compared. Each prefix comprises at least a portion of a plurality of sorted values. A respective prefix comprises a set of consecutive characters including at least a first character of a respective sorted value. The respective sorted value further comprising a respective suffix comprising consecutive characters of the respective sorted value that are after the respective prefix. At least a respective first character of the first prefix and a respective first character of the second prefix are determined to be substantially identical. The first prefix is merged with the second prefix into a single prefix comprising the first character. A set of suffixes associated with the first prefix is updated to reflect an association with the second prefix.

Abstract: A method and processor to determine distances between multiple index driven scan operations. A first anchor index entry is identified during a first index scan and stored. A first number of index entries between the first anchor index entry and a first index scan location being processed by a first index scan is determined based on information maintained external to an index structure. A determination is made of second number of index entries between the first anchor index entry and a second index scan location being processed by a second index scan executing concurrently with the first index scan based on information maintained external to the index structure. A distance between the first index scan location and the second index scan location is calculated as equal to a difference between the first number of index entries and the second number of index entries.

Abstract: An index scan processor and method to perform concurrent scans of stored indexed data. An indexed data scanner performs a first scan of stored data by sequentially scanning through an index data structure and maintains, over a duration of the first scan, a first scan current scan location within the index data structure that indicates a currently accessed record within the stored data structure for the first scan. A scan manager accepts a request for a second scan of the stored data, determines, during the performing the first scan, a starting index scan location within the index data structure for the second scan that is sufficiently near the first scan current index scan location to cause records indicated by the starting location index to be stored within a buffer due to the performing the first scan, and starts the second scan at the starting location and proceeding to the second end key.

Abstract: Disclosed are a method, information processing system, and computer readable medium for managing table scan processes. The method includes monitoring a plurality of storage medium table scan processes. Each storage medium table scan process in the plurality of storage medium table scan processes is placed into a plurality of scan groups based on storage medium pages to be scanned by each of the storage medium table scan processes. Each storage medium table scan process in a scan group can share data within a storage medium page.