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原文地址：https://www.sqlite.org/opcode.html1.执行摘要SQLite 通过将SQL语句翻译为字节码之后在虚拟机上运行该字节码的方式来工作。这篇文章来描述字节码引擎是如何工作的。这篇文章描述的是SQLite的内在。使用SQLite进行常规应用开发不需要此处提供的信息。这篇文章的目的是让人们更加深入了解SQLite的内部的运行机理。字节码引擎并不是SQ...

关于Bitvet/*A bitmap is an instance of the following structure.This bitmap records the existence of zero or more bitswith values between 1 and iSize, inclusive.There are three possible represent...

/*When SQLITE_OMIT_WSD is defined, it means that the target platform doesnot support Writable Static Data (WSD) such as global and static variables.All variables must either be on the stack or dyna...

/*2008 October 7The author disclaims copyright to this source code. In place ofa legal notice, here is a blessing:May you do good and not evil.May you find forgiveness for yourself and forgive o...

/*Free slots in the allocator used to divide up the global page cachebuffer provided using the SQLITE_CONFIG_PAGECACHE mechanism.*/struct PgFreeslot { PgFreeslot *pNext; /* Next free slot */};...

This module implements the sqlite3_status() interface and relatedfunctionality.*/#include "sqliteInt.h"#include "vdbeInt.h"/*Variables in which to record status information.*/#if SQLITE_PTR...

pcacheFetchFinishWithInit/*This is a helper routine for sqlite3PcacheFetchFinish()In the uncommon case where the page being fetched has not beeninitialized, this routine is invoked to do the ini...

/*2005 November 29The author disclaims copyright to this source code. In place ofa legal notice, here is a blessing:May you do good and not evil.May you find forgiveness for yourself and forgive...

PgHdr/*Every page in the cache is controlled by an instance of the followingstructure.*/struct PgHdr { sqlite3_pcache_page *pPage; /* Pcache object page handle */ void *pData; ...

/* Bit values for PgHdr.flags */如果换算成二进制的话，那么下表的各个标志的值分别为：0000 0000 00010000 0000 00100000 0000 01000000 0000 10000000 0001 00000000 0010 00000000 0100 0000#define PGHDR_CLEAN 0x...

1.2.8.5故障恢复the journal keeps an account of all write operations carried out by transaction on the database日志保存数据库上事务执行的所有写入操作的帐户Each log record has a header that is a descriptor for therecord, ...

pager.c文件中有Pager的定义struct Pager { sqlite3_vfs *pVfs; /* OS functions to use for IO */ u8 exclusiveMode; /* Boolean. True if locking_mode==EXCLUSIVE */ u8 journalMode;...

首先获取System.Data.SQLite支持然后使用SQLiteHelperusing System;using System.Collections.Generic;using System.Data.SQLite;using System.Data; namespace WindowsFormsApplication2{ public class...

B+树内部页格式分析指针数组内容为：0FFA0FF4 0FEE0FE8 0FE20FDC 0FD60FD0 0FCA0FC4 0FBE0FB8 0FB20FAC 0FA60FA0 0F9A指针数组指向的单元的内容为：0F9AH 地址：80900000 0013A177 （格式为：指针+key，即Ptr(0),Key(0)）0FA0H 地址：8096 ...

首先建表然后使用pyhton辅助生成插入数据的sql语句生成的sql语句如下：insert into stu values(NULL,'zhangsanaa');insert into stu values(NULL,'zhangsanab');insert into stu values(NULL,'zhangsanac');insert into stu values...

Pager是the page cache。不仅仅包含cache实体，而且包含cache的其他的属性。struct Pager { sqlite3_vfs *pVfs; /* OS functions to use for IO */ u8 exclusiveMode; /* Boolean. True if locking_mode==EXC...

sqlite3Malloc/*Allocate memory. This routine is like sqlite3_malloc() except that itassumes the memory subsystem has already been initialized.*/void *sqlite3Malloc(u64 n){ void *p; if( n==...

数据库最大页数 2^31如何找到一个指针所指向的内容？ 1、找到指针映射页面的页码(PTRMAP_PAGENO) 2、找到对应指针的偏移(PTRMAP_PTROFFSET)指针映射的目的是什么？ 将页面从文件中的一个位置移动到另一个位置，旧页更新后，必须更新原旧页的父级中的指针指向新位置每个SQLite表必须设置btree_intkey或...

pcache1Unpin/*Implementation of the sqlite3_pcache.xUnpin method.Mark a page as unpinned (eligible for asynchronous recycling).*/最后一步*ppFirst = pPage最终结尾。ppFirst是指向PgHdr1指针的指针。ppFirst一直没有变，但是p...