# 下載源碼
wget https://sqlite.org/2023/sqlite-amalgamation-3420000.zip
unzip sqlite-amalgamation-3420000.zip
# 配置交叉編譯
export CC=arm-linux-gnueabihf-gcc
./configure --host=arm-linux --prefix=/opt/sqlite-embedded
# 編譯安裝
make
make install

// 在 sqlite3.c 中添加編譯選項(xiàng)
#define SQLITE_OMIT_DECLTYPE       // 節(jié)省 1.5KB
#define SQLITE_OMIT_DEPRECATED     // 節(jié)省 0.8KB
#define SQLITE_OMIT_PROGRESS_CALLBACK // 節(jié)省 0.3KB
#define SQLITE_OMIT_LOAD_EXTENSION // 節(jié)省 20KB
#define SQLITE_THREADSAFE 0        // 單線程模式

// 系統(tǒng)啟動(dòng)時(shí)配置
sqlite3_config(SQLITE_CONFIG_MEMSTATUS, 0);  // 禁用內(nèi)存統(tǒng)計(jì)
sqlite3_config(SQLITE_CONFIG_SCRATCH, NULL, 0, 0); // 禁用臨時(shí)內(nèi)存
sqlite3_config(SQLITE_CONFIG_PAGECACHE, buffer, 1024, 10); // 自定義緩存

#include <sqlite3.h>
#include <stdio.h>
#define DB_FILE "/flash/data/sensor.db"
int main() {
    sqlite3 *db;
    char *err_msg = 0;
    // 打開數(shù)據(jù)庫(kù)（不存在則創(chuàng)建）
    int rc = sqlite3_open(DB_FILE, &db);
    if (rc != SQLITE_OK) {
        fprintf(stderr, "Can't open database: %s\n", sqlite3_errmsg(db));
        return 1;
    }
    // 創(chuàng)建表
    const char *sql = "CREATE TABLE IF NOT EXISTS SensorData("
                      "id INTEGER PRIMARY KEY AUTOINCREMENT,"
                      "sensor_id INTEGER NOT NULL,"
                      "value REAL,"
                      "timestamp DATETIME DEFAULT CURRENT_TIMESTAMP);";
    rc = sqlite3_exec(db, sql, 0, 0, &err_msg);
    if (rc != SQLITE_OK) {
        fprintf(stderr, "SQL error: %s\n", err_msg);
        sqlite3_free(err_msg);
    }
    // 插入傳感器數(shù)據(jù)
    sql = "INSERT INTO SensorData(sensor_id, value) VALUES(101, 25.3);"
          "INSERT INTO SensorData(sensor_id, value) VALUES(102, 60.8);";
    rc = sqlite3_exec(db, sql, 0, 0, &err_msg);
    // 錯(cuò)誤處理同上
    // 查詢數(shù)據(jù)
    sqlite3_stmt *stmt;
    sql = "SELECT sensor_id, value, timestamp FROM SensorData WHERE value > ?;";
    rc = sqlite3_prepare_v2(db, sql, -1, &stmt, 0);
    if (rc == SQLITE_OK) {
        sqlite3_bind_double(stmt, 1, 30.0); // 綁定參數(shù)
        while (sqlite3_step(stmt) == SQLITE_ROW) {
            int sensor_id = sqlite3_column_int(stmt, 0);
            double value = sqlite3_column_double(stmt, 1);
            const char *time = (const char*)sqlite3_column_text(stmt, 2);
            printf("Sensor %d: %.1f at %s\n", sensor_id, value, time);
        }
    }
    sqlite3_finalize(stmt);
    // 關(guān)閉數(shù)據(jù)庫(kù)
    sqlite3_close(db);
    return 0;
}

// 批量插入1000條數(shù)據(jù)
void batch_insert(sqlite3 *db) {
    sqlite3_exec(db, "BEGIN TRANSACTION;", 0, 0, 0);
    sqlite3_stmt *stmt;
    const char *sql = "INSERT INTO SensorData(sensor_id, value) VALUES(?, ?);";
    sqlite3_prepare_v2(db, sql, -1, &stmt, 0);
    for (int i = 0; i < 1000; i++) {
        sqlite3_bind_int(stmt, 1, 200 + i % 5);
        sqlite3_bind_double(stmt, 2, 20.0 + (i % 30));
        if (sqlite3_step(stmt) != SQLITE_DONE) {
            // 錯(cuò)誤處理
        }
        sqlite3_reset(stmt);
    }
    sqlite3_finalize(stmt);
    sqlite3_exec(db, "COMMIT;", 0, 0, 0);
}

// 配置數(shù)據(jù)庫(kù)參數(shù)
void configure_db(sqlite3 *db) {
    // 設(shè)置WAL模式（Write-Ahead Logging）
    sqlite3_exec(db, "PRAGMA journal_mode=WAL;", 0, 0, 0);
    // 設(shè)置同步模式為NORMAL（平衡性能與安全）
    sqlite3_exec(db, "PRAGMA synchronous=NORMAL;", 0, 0, 0);
    // 設(shè)置頁(yè)大?。ㄆヅ銯lash存儲(chǔ)塊）
    sqlite3_exec(db, "PRAGMA page_size=4096;", 0, 0, 0);
    // 設(shè)置緩存大?。ǜ鶕?jù)可用內(nèi)存調(diào)整）
    sqlite3_exec(db, "PRAGMA cache_size=-2000;", 0, 0, 0); // 2000KB
}

// 自定義內(nèi)存分配函數(shù)
void* embedded_malloc(int n) {
    return malloc(n);
}
void embedded_free(void *p) {
    free(p);
}
// 初始化時(shí)設(shè)置
sqlite3_config(SQLITE_CONFIG_MALLOC, embedded_malloc, embedded_free);

// 對(duì)于固化的配置數(shù)據(jù)庫(kù)
sqlite3_open_v2("config.db", &db, SQLITE_OPEN_READONLY, NULL);
// 設(shè)置優(yōu)化參數(shù)
sqlite3_exec(db, "PRAGMA query_only=ON;", 0, 0, 0);
sqlite3_exec(db, "PRAGMA locking_mode=EXCLUSIVE;", 0, 0, 0);

// 在線備份到SD卡
void backup_database() {
    sqlite3 *backup_db;
    sqlite3_open("/sd/backup.db", &backup_db);
    sqlite3_backup *pBackup = sqlite3_backup_init(backup_db, "main", db, "main");
    if (pBackup) {
        sqlite3_backup_step(pBackup, -1); // 復(fù)制所有數(shù)據(jù)
        sqlite3_backup_finish(pBackup);
    }
    sqlite3_close(backup_db);
}
// 恢復(fù)數(shù)據(jù)庫(kù)
void restore_database() {
    sqlite3_close(db);
    copy_file("/sd/backup.db", DB_FILE);
    sqlite3_open(DB_FILE, &db);
}

// 啟動(dòng)時(shí)配置
sqlite3_config(SQLITE_CONFIG_HEAP, heap_buffer, HEAP_SIZE, HEAP_MIN);
sqlite3_config(SQLITE_CONFIG_SCRATCH, scratch_buffer, 512, 5);
sqlite3_config(SQLITE_CONFIG_PAGECACHE, page_buffer, 1024, 2);
// 數(shù)據(jù)庫(kù)參數(shù)
PRAGMA page_size = 512;
PRAGMA cache_size = 5;  // 5頁(yè)緩存
PRAGMA temp_store = MEMORY;

// 創(chuàng)建內(nèi)存數(shù)據(jù)庫(kù)
sqlite3_open(":memory:", &mem_db);
// 從文件加載到內(nèi)存
sqlite3_exec(db, "ATTACH DATABASE ':memory:' AS mem;", 0, 0, 0);
sqlite3_exec(db, "CREATE TABLE mem.data AS SELECT * FROM main.SensorData;", 0, 0, 0);
// 操作內(nèi)存數(shù)據(jù)庫(kù)
sqlite3_exec(mem_db, "SELECT * FROM data;", callback, 0, 0);

// 實(shí)現(xiàn)VFS接口
static sqlite3_vfs embedded_vfs = {
    .szOsFile = sizeof(EmbeddedFile),
    .xOpen = embeddedOpen,
    .xDelete = embeddedDelete,
    .xAccess = embeddedAccess,
    // ... 其他方法
};
// 注冊(cè)VFS
sqlite3_vfs_register(&embedded_vfs, 1);
// 使用自定義VFS打開數(shù)據(jù)庫(kù)
sqlite3_open_v2("file:/flash/data.db", &db, SQLITE_OPEN_READWRITE, "embedded");

// 創(chuàng)建傳感器數(shù)據(jù)表
CREATE TABLE sensor_readings (
    timestamp INTEGER PRIMARY KEY,  // Unix時(shí)間戳
    sensor_id INTEGER,
    value REAL,
    status INTEGER CHECK(status IN (0,1))  // 0=正常,1=異常
);
// 創(chuàng)建空間優(yōu)化索引
CREATE INDEX idx_sensor_time ON sensor_readings(sensor_id, timestamp);

// 鍵值對(duì)配置表
CREATE TABLE device_config (
    key TEXT PRIMARY KEY,
    value TEXT,
    last_modified TIMESTAMP DEFAULT CURRENT_TIMESTAMP
);
// 初始化配置
INSERT OR IGNORE INTO device_config(key, value) VALUES
    ('device_id', 'SN-12345'),
    ('sampling_interval', '5000'),
    ('transmit_mode', 'gprs');

// 循環(huán)日志表（自動(dòng)覆蓋舊數(shù)據(jù)）
CREATE TABLE event_log (
    id INTEGER PRIMARY KEY AUTOINCREMENT,
    severity INTEGER,  // 1=Debug, 2=Info, 3=Error
    message TEXT,
    timestamp DATETIME DEFAULT CURRENT_TIMESTAMP
);
// 自動(dòng)清理舊日志的觸發(fā)器
CREATE TRIGGER log_cleanup AFTER INSERT ON event_log
BEGIN
    DELETE FROM event_log 
    WHERE id <= (SELECT id FROM event_log ORDER BY id DESC LIMIT 1 OFFSET 1000);
END;

int rc = sqlite3_exec(db, sql, 0, 0, &err_msg);
if (rc != SQLITE_OK) {
    if (rc == SQLITE_CORRUPT) {
        // 數(shù)據(jù)庫(kù)損壞處理
        repair_database();
    } else if (rc == SQLITE_FULL) {
        // 存儲(chǔ)空間不足
        handle_storage_full();
    } else {
        log_error("DB error %d: %s", rc, err_msg);
    }
    sqlite3_free(err_msg);
}

// 定期檢查數(shù)據(jù)庫(kù)完整性
int check_database_integrity(sqlite3 *db) {
    sqlite3_stmt *stmt;
    sqlite3_prepare_v2(db, "PRAGMA integrity_check;", -1, &stmt, 0);
    while (sqlite3_step(stmt) == SQLITE_ROW) {
        const char *result = (const char*)sqlite3_column_text(stmt, 0);
        if (strcmp(result, "ok") != 0) {
            log_error("Database corruption: %s", result);
            return 0; // 失敗
        }
    }
    sqlite3_finalize(stmt);
    return 1; // 成功
}

// 啟用性能分析
sqlite3_exec(db, "PRAGMA temp_store=MEMORY;", 0, 0, 0);
sqlite3_exec(db, "PRAGMA stats=on;", 0, 0, 0);
// 獲取性能數(shù)據(jù)
sqlite3_stmt *stmt;
sqlite3_prepare_v2(db, "SELECT * FROM sqlite_stats;", -1, &stmt, 0);
while (sqlite3_step(stmt) == SQLITE_ROW) {
    printf("Table: %s, Index: %s, Stat: %s\n",
           sqlite3_column_text(stmt, 0),
           sqlite3_column_text(stmt, 1),
           sqlite3_column_text(stmt, 2));
}