Query Execution
PROJECT #3 - QUERY EXECUTION
่ฟไธช project ไธป่ฆๆฏๅฎ็ฐๅขๅ ๅฏนๆฐๆฎๅบ็ณป็ป็ๆง่ก่ฎกๅ็ๆฏๆใ้่ฆๅฎ็ฐๅ็ง executors๏ผๅฐ query plan ไผ ๅ ฅ executors ็ถๅๆง่กๅฎไปฌใ้่ฆๅฎ็ฐไธๅ็ executors๏ผ
Access Methods: Sequential Scans, Index Scans
Modifications: Inserts, Updates, Deletes
Miscellaneous: Nested Loop Joins, Index Nested Loop Joins, Aggregation, Limit/Offset
ๆไปฌ้่ฆๅฎ็ฐ่ฟญไปฃๆฅ่ฏขๅค็ๆจกๅ๏ผๆฏไธชๆฅ่ฏข่ฎกๅๆง่กๅจๅฎ็ฐไบไธไธช Init() ๅฝๆฐๅ Next() ๅฝๆฐใๅฝ DBMS ่ฐ็จ executors ็ Next() ๅฝๆฐๆถ๏ผๅฎไผ่ฟๅ
ไธไธช
tupleๅนถ่ฟๅtrueๆฒกๆ
tupleๅฏไปฅๅ่ฟๅๆถ๏ผ่ฟๅfalse
TASK #1 - SYSTEM CATALOG
่ฟไธช task ไธ้พ๏ผไธป่ฆๆฏๅฎ็ฐ
src/include/catalog/catalog.hๆไปถ๏ผcatalog ็ปดๆคไบๆฐๆฎๅบ็ meta-data๏ผไธญ็่ฆๆฑๅฎ็ฐ็ๅฝๆฐ๏ผ่ฟไบๅฝๆฐไธๆฐๆฎๅบ็่กจๅ็ดขๅผๆๅ ณใ
GetTable()ไฝฟ็จstd::unordered_map็atๅฝๆฐ๏ผๅฎไผๅไธๆ ๆฃๆฅ๏ผๅฝkeyไธๅญๅจๆถไผๆๅบๅผๅธธๅจ
CreateIndexๅฝๆฐไธญ๏ผๅๅปบ่กจ็็ดขๅผๆถ๏ผ้่ฆไฝฟ็จ table heap ็่ฟญไปฃๅจๅๅบๆฏไธช tuple๏ผ็ถๅไฝฟ็จ tuple ็KeyFromTupleๆ้ key tuple ๆๅ ฅๅฐ B+ Tree ไธญ
TASK #2 - EXECUTORS
SEQUENTIAL SCAN
ๅจ้กบๅบๆง่กๅจไธญ๏ผๅฆไฝไฟๅญ
table_heap_็่ฟญไปฃๅจๅข๏ผไธ็ดๆฒกๆพๅฐ่งฃๅณๆนๆก๏ผๅ ไธบๆๅ ้ๆฉๅจไฝฟ็จstd::vector<Tuple>ๅ ไฟๅญ็ปๆ๏ผ็ถๅๅจNextไธญไธไธชไธไธช่ฟๅใๅจ่ฟๅ็ปๆๆถ๏ผ่ฎฐๅพ่ฆๆ นๆฎOutputSchemaๆ้ tuple ่ฟๅ
INDEX SCANS
้่ฟ B+ Tree ็ดขๅผ๏ผๅ ่ทๅพ
RID๏ผ็ถๅๆ นๆฎRIDๅจtable_heap_ไธญๅพๅฐๅฏนๅบ็ tuple
้่ฟ
dynamic_cast<BPlusTreeIndex<GenericKey<8>, RID, GenericComparator<8>> *>(indexInfo_->index_.get());ๅฐIndex่ฝฌๆBPlusTreeIndex็ฑปๅ
INSERT
ๆๅ ฅๆง่กๅจ้่ฆๅบๅๅพ ๆๅ ฅ็ๆฐๆฎๆฏ
RawInsert่ฟๆฏๆฅ่ชchild_executor_ๅฆๆๅพ ๆๅ ฅ็่กจๅญๅจ็ดขๅผ้่ฆไฝฟ็จ
KeyFromTupleๆ้index_key๏ผ็ถๅๅฐๅฎๆๅ ฅๅฐ B+ Tree ็ดขๅผไธญengine ๅจๆๅ ฅใๆดๆฐใๅ ้คไธ้่ฆๅฐ tuple ๆทปๅ ๅฐ
result_setไธญ๏ผๅฆๅๅจ test ไธญไผๆฅresult_setไธไธบ็ฉบ็้่ฏฏ
UPDATE
็ฑ
child_executor_็Nextๆไพ tuple๏ผ็ถๅ่ฐ็จGenerateUpdatedTuple็ๆๅพ ๆดๆฐ็ tuple๏ผๆๅไฝฟ็จtable_heap_->UpdateTuple่ฟ่กๆดๆฐๆไฝ
DELETE
็ฑ
child_executor_็Nextๆไพ tuple่ฐ็จ
table_heap_->MarkDeleteๆ ่ฎฐ่ฟไธช tuple ้่ฆๅ ้คๅฆๆๅพ ๆๅ ฅ็่กจๅญๅจ็ดขๅผ้่ฆไฝฟ็จ
KeyFromTupleๆ้index_key๏ผ็ถๅๅจ B+ Tree ็ดขๅผไธญๅฐ่ฟไธช Key ๅ ้ค
NESTED LOOP JOIN
ไฝฟ็จ
left_executorๅright_executorๆไพ็ tuple ่ฟ่กEvaluateJoinๆ้ ็ฌฆๅๆกไปถ็ tuple
INDEX NESTED LOOP JOIN
ไฝฟ็จ็ดขๅผๆฅ่ฟ่ก Join๏ผ่ฟๆ ทๅฐฑไธ้่ฆๆซๆๆดไธช inner tableใๅ ๆญคๆไปฌ้่ฆๅฐ outer tuple ่ฝฌๅไธบๅฏนๅบ็
key๏ผ็ถๅๅจ inner table index ไธญ่ฟ่กๆฅๆพใ
ๆต่ฏ/้ช่ฏ/ๆๅ
ๆต่ฏ
ๆ ผๅผ้ช่ฏ
ๆๅ
็ถๅๅๅพ https://www.gradescope.com ๆไบคไปฃ็
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