Analytics Spring 2020 4/16: Skew mitigation Vasiliki (Vasia) Kalavri vkalavri@bu.edu ## Key partitioning  • Items are - To address skew, the system needs to track the frequencies of the partitioning key values. • We can then use a hybrid partitioning function that treats normal keys and popular keys differently. • Keeping

Row Security Policies ..... 84 5.9. Schemas ..... 90 5.10. Inheritance ..... 95 5.11. Table Partitioning ..... 99 5.12. Foreign Data ..... 113 5.13. Other Database Objects ..... 113 5.14. Dependency Database Object Location Functions ..... 419 9.96. Collation Management Functions ..... 420 9.97. Partitioning Information Functions ..... 420 9.98. Index Maintenance Functions ..... 421 9.99. Generic Setting up a Partial Unique Index ..... 453 11.4. Do Not Use Partial Indexes as a Substitute for Partitioning ..... 453 21.1. Example pg_hba.conf Entries ..... 708 21.2. An Example pg_ident.conf File

sensitive to that parameter. Partitioning of big collections and the proper use of GiST and GIN indexes allows the implementation of very fast searches with online update. Partitioning can be done at the database collecting statistics. - Does the optimizer selectively scan partitioned tables? If you use table partitioning, is the optimizer selectively scanning only the child tables required to satisfy the query predicates enabled, you cannot use STABLE or VOLATILE functions in an UPDATE statement. • Greenplum Database partitioning columns cannot be updated. ## Deleting Rows The DELETE command deletes rows from a table. Specify

43 6.3.4 分割區與選擇掛載點 ..... 44 6.3.4.1 Supported partitioning options ..... 44 6.3.4.2 Guided Partitioning ..... 45 6.3.4.3 Manual Partitioning ..... 46 6.3.4.4 Configuring Multidisk Devices (Software 5 Account setup 80 B.4.6 Clock and time zone setup 81 B.4.7 Partitioning 81 B.4.7.1 Partitioning example 81 B.4.7.2 Partitioning using RAID 83 B.4.7.3 Controlling how partitions are mounted 84 directly from a Debian server (if you are not installing from a set of DVD installation images), partitioning your hard drives and installation of a base system, then selection and installation of tasks.

Privileges … 77 5.8. Row Security Policies … 82 5.9. Schemas … 89 5.10. Inheritance … 93 5.11. Table Partitioning … 97 5.12. Foreign Data … 111 5.13. Other Database Objects … 112 5.14. Dependency Tracking … 112 91. Database Object Location Functions … 400 9.92. Collation Management Functions … 401 9.93. Partitioning Information Functions … 401 9.94. Index Maintenance Functions … 402 9.95. Generic File Access Setting up a Partial Unique Index … 433 11.4. Do Not Use Partial Indexes as a Substitute for Partitioning … 434 20.1. Example pg_hba.conf Entries … 678 20.2. An Example pg_ident.conf File … 681 33.1.

… 83 5.9. Row Security Policies … 88 5.10. Schemas … 94 5.11. Inheritance … 99 5.12. Table Partitioning … 103 5.13. Foreign Data … 117 5.14. Other Database Objects … 118 5.15. Dependency Tracking … 101. Database Object Location Functions … 450 9.102. Collation Management Functions … 450 9.103. Partitioning Information Functions … 451 9.104. Index Maintenance Functions … 451 9.105. Generic File Access Setting up a Partial Unique Index … 483 11.4. Do Not Use Partial Indexes as a Substitute for Partitioning … 484 20.1. Example pg_hba.conf Entries … 754 20.2. An Example pg_ident.conf File … 758 32.1.

use entire disk” partitioning method.  Partition disks The installer can guide you through partitioning a disk (using different prefer, you can do it manually. With guided partitioning you will still have a chance later to review and customise the results. If you choose guided partitioning for an entire disk, you will next be asked asked which disk should be used. Partitioning method: Guided - use entire disk Guided - use entire disk and set up LVM Manual Guided - use entire disk and set up encrypted LVM Go Back - Select the storage

Privileges … 77 5.9. Row Security Policies … 82 5.10. Schemas … 88 5.11. Inheritance … 93 5.12. Table Partitioning … 96 5.13. Foreign Data … 110 5.14. Other Database Objects … 110 5.15. Dependency Tracking Management Functions … 428 9.105. Database Object Statistics Manipulation Functions … 429 9.106. Partitioning Information Functions … 431 9.107. Index Maintenance Functions … 431 9.108. Generic File Access Setting up a Partial Unique Index … 463 11.4. Do Not Use Partial Indexes as a Substitute for Partitioning … 464 20.1. Example pg_hba.conf Entries … 729 20.2. An Example pg_ident.conf File … 733 32.1.

Settings 468 Dropping a Table 469 Partitioning Large Tables 469 About Table Partitioning 469 Table Partitioning in Greenplum Database 470 Deciding on a Table Partitioning Strategy 470 Creating Partitioned Table Partitions 472 Defining List Table Partitions 473 Defining Multi-level Partitions 473 Partitioning an Existing Table 474 Limitations of Partitioned Tables 474 Loading Partitioned Tables 475 Verifying Oriented Storage 1025 Compression 1025 Distributions 1026 Resource Queue Memory Management 1026 Partitioning 1027 Indexes 1028 Resource Queues 1028 Monitoring and Maintenance 1028 ANALYZE 1029 Vacuum

c1ba296d646f0867cc51cc11426/p5_1.jpg) Relay IR Graph Annotation with Your Annotator Graph Partitioning Your Codegen Serialized Subgraph Library LLVM, CUDA, Metal, VTA Relay Runtime (VM, Graph 1ba296d646f0867cc51cc11426/p10_1.jpg) Relay IR Graph Annotation with Your Annotator Graph Partitioning Your Codegen Serialized Subgraph Library LLVM, CUDA, Metal, VTA Relay Runtime (VM, Graph Implement a graph annotator ## Partition the Relay IR graph • No user involvement ## Graph Partitioning ## Use external functions to wrap annotated subgraphs ![Image](/uploads/documents/7/a/0/c/7