本文介紹了iOS 原生sqlite3的使用方法,分享給大家,具體如下:
SQLite?
SQL語句常用操作
增、刪、改、查,CRUD,Create[新建], Retrieve[檢索], Update[更新], Delete[刪除]。
SQL語法寫法特點
1、不區分大小寫(CREATE = create)
2、每條語句以分號(;)結尾
3、關鍵字建議大寫
SQL語句常用關鍵字
select、insert、update、delete、from、create、where、desc、order、by、group、table、alter、view、index等
// ViewController.m// sqlite3//// Created by 周玉 on 2017/12/13.// Copyright © 2017年 guidekj. All rights reserved.//#import "ViewController.h"#import <sqlite3.h>#define KUIScreenWidth [UIScreen mainScreen].bounds.size.width#define KUIScreenHeight [UIScreen mainScreen].bounds.size.height#define FILE_NAME @"saas.sqlite"static sqlite3 *db = nil;@interface ViewController ()@end@implementation ViewController- (void)viewDidLoad { [super viewDidLoad]; self.title = @"sqlite3"; //DDB// [self openDB];// [self closeDB]; //DDL// [self createTable];// [self dropTable]; //DML// [self insertData];// [self updateData];// [self deleteData]; //DQL [self queryData];}#pragma mark 查詢- (void)queryData{ sqlite3 *newDB = [self openDB]; sqlite3_stmt *statement = nil; NSString *sqlStr = @"SELECT * FROM SAAS_PERSON"; int result = sqlite3_prepare_v2(newDB, sqlStr.UTF8String, -1, &statement, NULL); if (result == SQLITE_OK) { //遍歷查詢結果 if (!(sqlite3_step(statement) == SQLITE_DONE)) { while (sqlite3_step(statement) == SQLITE_ROW) { int ID = sqlite3_column_int(statement, 0); const unsigned char *name = sqlite3_column_text(statement, 1); const unsigned char *sex = sqlite3_column_text(statement, 2); int age = sqlite3_column_int(statement, 3); const unsigned char *description = sqlite3_column_text(statement, 4); NSLog(@"ID = %d , name = %@ , sex = %@ , age = %d , description = %@",ID,[NSString stringWithUTF8String:(const char *)name],[NSString stringWithUTF8String:(const char *)sex],age,[NSString stringWithUTF8String:(const char *)description]); } } else { NSLog(@"查詢語句完成"); } } else { NSLog(@"查詢語句不合法"); } sqlite3_finalize(statement); [self closeDB];}#pragma mark 刪除數據記錄- (void)deleteData{ sqlite3 *newDB = [self openDB]; sqlite3_stmt *statement = nil; NSString *sqlStr = @"DELETE FROM SAAS_PERSON WHERE NAME = '王鵬飛'"; int result = sqlite3_prepare_v2(newDB, sqlStr.UTF8String, -1, &statement, NULL); if (result == SQLITE_OK) { if (sqlite3_step(statement) == SQLITE_DONE) { NSLog(@"刪除操作完成"); } } else { NSLog(@"刪除操作不合法"); } sqlite3_finalize(statement); [self closeDB];}#pragma mark 更新數據記錄- (void)updateData{ sqlite3 *newDB = [self openDB]; sqlite3_stmt *statement = nil; NSString *sqlStr = @"UPDATE SAAS_PERSON SET DESCRIPTION = '喜歡運動,旅游' WHERE NAME = '周玉'"; int result = sqlite3_prepare_v2(newDB, sqlStr.UTF8String, -1, &statement, NULL); if (result == SQLITE_OK) { if (sqlite3_step(statement) == SQLITE_DONE) { NSLog(@"更新信息完成"); } } else { //[logging] no such column: DESCRIPT (KEY拼寫錯誤) --- 更新信息不合法 NSLog(@"更新信息不合法"); } sqlite3_finalize(statement); [self closeDB];}#pragma mark 新增數據記錄- (void)insertData{ sqlite3 *newDB = [self openDB]; sqlite3_stmt *statement = nil;// NSString *sqlStr = @"INSERT INTO SAAS_PERSON (NAME , SEX , AGE , DESCRIPTION) VALUES('周玉','男',28,'開朗樂觀')";// NSString *sqlStr = @"INSERT INTO SAAS_PERSON (NAME , SEX , AGE , DESCRIPTION) VALUES('王鵬飛','女',27,'開朗樂觀')";// NSString *sqlStr = @"INSERT INTO SAAS_PERSON (NAME , SEX , AGE , DESCRIPTION) VALUES('李梅','女',20,'年輕可愛��')"; NSString *sqlStr = @"INSERT INTO SAAS_PERSON (NAME , SEX , AGE , DESCRIPTION) VALUES('sumit','男',15,'小朋友的年紀')"; //檢驗合法性 int result = sqlite3_prepare_v2(newDB, sqlStr.UTF8String, -1, &statement, NULL); if (result == SQLITE_OK) { //判斷語句執行完畢 if (sqlite3_step(statement) == SQLITE_DONE) { NSLog(@"插入的信息完成"); } } else { NSLog(@"插入的信息不合法"); } sqlite3_finalize(statement); [self closeDB];}#pragma mark 創建表- (void)createTable{ sqlite3 *newDB = [self openDB]; // char *sql = "CREATE TABLE IF NOT EXISTS t_person (ID INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, NAME TEXT , SEX TEXT,AGE INTEGER,DESCRIPTION TEXT);"; NSString *sqlStr = @"CREATE TABLE IF NOT EXISTS SAAS_PERSON (ID INTEGER PRIMARY KEY AUTOINCREMENT NOT NULL, NAME TEXT , SEX TEXT,AGE INTEGER,DESCRIPTION TEXT);"; char *error = NULL; int result = sqlite3_exec(newDB, sqlStr.UTF8String, NULL, NULL, &error); if (result == SQLITE_OK) { NSLog(@"創建表成功"); } else { NSLog(@"創建表失敗 = %s",error); } [self closeDB];}#pragma mark 刪除表- (void)dropTable{ sqlite3 *newDB = [self openDB]; NSString *sqlStr = @"DROP TABLE t_person"; char *error = NULL; int result = sqlite3_exec(newDB, sqlStr.UTF8String, NULL, NULL, &error); if (result == SQLITE_OK) { NSLog(@"刪除表成功"); } else { NSLog(@"刪除表失敗 = %s",error); } [self closeDB];}#pragma mark 打開或者創建數據庫- (sqlite3 *)openDB { if (!db) { //1.獲取document文件夾的路徑 //參數1:文件夾的名字 參數2:查找域 參數3:是否使用絕對路徑 NSString *documentPath = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES)[0]; //獲取數據庫文件的路徑 NSString *dbPath = [documentPath stringByAppendingPathComponent:@"saas.sqlite"]; NSLog(@"%@",dbPath); //判斷document中是否有sqlite文件 int result = sqlite3_open([dbPath UTF8String], &db); if (result == SQLITE_OK) { NSLog(@"打開數據庫"); }else{ [self closeDB]; NSLog(@"打開數據庫失敗"); } } return db;}#pragma mark 關閉數據庫- (void)closeDB{ int result = sqlite3_close(db); if (result == SQLITE_OK) { NSLog(@"數據庫關閉成功"); db = nil; } else { NSLog(@"數據庫關閉失敗"); }}@end
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