接前面，看 SeqNext 函数：/* ---------------------------------------------------------------- * SeqNext * * This is a workhorse for ExecSeqScan * ---------------------------------------------------------------- */static TupleTableSlot *SeqNext(SeqScanState *node){ HeapTuple tuple; Heap...
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2013-05-31 17:30:00
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全表遍历预备知识《PostgreSQL 流程—查询》概述在《PostgreSQL 流程—查询》我们重点讨论了PostgreSQL的查询流程，提到全表遍历的操作主要有函数SeqNext来实现，本文将重点讨论SeqNext的流程。SeqNextSeqNext的代码比较短，我们直接来看代码：static TupleTableSlot *
SeqNext(SeqScanState *node)
{
He
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2024-10-03 14:25:01
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在src/backend/executor/nodeSeqscan.c文件中的SeqNext函数会调用table_beginscan函数
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2022-12-31 08:24:00
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接前面，看被SeqNext所调用的heap_getnext：HeapTupleheap_getnext(HeapScanDesc scan, ScanDirection direction){ /* Note: no locking manipulations needed */ HEAPDEBUG_1; /* heap_getnext( info ) */ if (scan->rs_pageatatime) heapgettup_pagemode(scan, direction,scan->rs_nkeys, scan->rs_k...
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2013-06-03 10:13:00
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