数据库存在的意义就是对数据进行整合和管理,即对数据进行增,删,改,查的操作。
1.创建表的格式为
create table 表名(参数名1 类型 修饰条件,参数名2,类型 修饰参数,···)
sqlite中支持如下的类型:
smallint 短整型
integer 整型
real 实数型
float 单精度浮点
double 双精度浮点
currency 长整型
varchar 字符型
text 字符串
binary 二进制数据
blob 二进制大对象
boolean 布尔类型
date 日期类型
time 时间类型
timestamp 时间戳类型
关于修饰条件,常用的有如下几种:
PRIMARY KEY:将本参数这个为主键,主键的值必须唯一,可以作为数据的索引,例如编号。
NOT NULL :标记本参数为非空属性。
UNIQUE:标记本参数的键值唯一,类似主键。
DEFAULT:设置本参数的默认值
CHECK:参数检查条件,例如上面代码,写入数据是count必须大于时才有效
2.添加数据格式如下
insert into 表名(键1,键2,···) values(值1,值2,···)
3.修改数据的格式如下
update 表名 set 键1=值1,键2=值2 where 条件--即修改数据的条件
4.删除数据的格式
delete from 表名 where 条件
5.删除一张表的格式
drop table 表名
6.查询操作的格式
select 键名,键名··· from 表名
select 键名,键名,··· from 表名 order by 键名 排序方式
order by 后面写要进行排序的键名,排序方式有 asc升序 desc降序
查找数据条数与查找位置限制:select 键名 from 表名 limit 最大条数 offset 查询起始位置
条件查询:select 键名 from 表名 where 条件
去重查询:select distinct 键名 from 表名
总结类----
#import#import/** *sql数据库支持的类型宏定义 */#define YHBASE_SQL_DATATYPE_SMALLINT @"smallint" //short#define YHBASE_SQL_DATATYPE_INTRGER @"integer" //int#define YHBASE_SQL_DATATYPE_REAL @"real" //实数#define YHBASE_SQL_DATATYPE_FLOAT @"float" //float#define YHBASE_SQL_DATATYPE_DOUBLE @"double" //double#define YHBASE_SQL_DATATYPE_CURRENCY @"currency" //long#define YHBASE_SQL_DATATYPE_VARCHAR @"varchar" //char#define YHBASE_SQL_DATATYPE_TEXT @"text" //string#define YHBASE_SQL_DATATYPE_BINARY @"binary" //二进制#define YHBASE_SQL_DATATYPE_BLOB @"blob" //长二进制#define YHBASE_SQL_DATATYPE_BOOLEAN @"boolean" //bool#define YHBASE_SQL_DATATYPE_DATE @"date" //日期#define YHBASE_SQL_DATATYPE_TIME @"time" //时间#define YHBASE_SQL_DATATYPE_TIMESTAMP @"timestamp"//时间戳#define YHBASE_SQL_ORDERTYPE_ASC @"asc" //升序
#define YHBASE_SQL_ORDERTYPE_DESC @"desc"
//降序@interface Sqlite3Context : NSObject/** 操作的数据库名称 */
@property (nonatomic, strong) NSString* name;
/** sqlite3对象 */@property (nonatomic, assign) sqlite3* sqlite3_db
;/** 1. 打开一个数据库 不存在则创建
2.path:数据库路径
3.return 是否操作成功 */
- (BOOL)openDataBaeWithName:(NSString* )path;
/** 1.在数据库中创建一张表,如果已经存在,则返回错误信息
2.表的名称
3.表中的键 其中的字典中需传入 键名:类型
4.calllBack 结果回调 */
- (void)createTableWithName:(NSString* )name keysDictionary:(NSDictionary*)dic callBack:(void (^)(Sqlite3Context* error))complete;/**
1.向表中添加一条数据 2.添加数据的键值对 3.插入表的名称 4.complete回调 */
- (void)insertData:(NSDictionary*)dataDict intoTable:(NSString* )name callBack:(void (^)(Sqlite3Context* error))complete;/**
1.向表中添加一个键 2.keyName-添加的键 3.type-类型 4.tableName--表名称 5.complete --结果回调 */
- (void)addKey:(NSString *)keyName keyType:(NSString *)type intoTable:(NSString *)tableName callBack:(void (^)(Sqlite3Context *error))complete;
/** 1.修改数据 2.dataDict --新的键值 3.whileStr--- 条件字符串 一般通过主键找到对应数据修改 可以为nil 4.complete---结果回调 */
- (void)update:(NSDictionary*)dataDict inTable:(NSString* )tableName whileString:(NSString*)whileStr callBack:(void(^)(Sqlite3Context *error))complete;
/** 1.删除数据 2.tableName 表名 3.whileStr 条件字符串 一般通过主键找到对应数据删除 可以为nil 不传这个参数将删除所有数据
*/- (void)deleteDataFromTable:(NSString *)tableName whereString:(NSString *)whileStr callBack:(void (^)(Sqlite3Context* error))complete;
/** 1.删除一张表 2.tableName--表名 */- (void)dropTable:(NSString *)tableName callBack:(void(^)(Sqlite3Context* error))complete;
/** 1.查询数据 2.keys ---要查询的键值 及其对应的数据类型 如果为nil则查询全部 3.tableName --表名 4.orderKey 进行排序的键值 如果为nil,则不排序 5.type 排序方式 6。whileStr查询条件 等同于查询单个数据 7.complete - dataArray 为查询到的数据 其内为字典 */
- (void)selectKeys:(NSArray*)keys fromTable:(NSString *)tableName orderBy:(NSString *)orderKey orderType:(NSString* )type whileStr:(NSString *)whileStr callBack:(void(^)(NSArray* dataArray,Sqlite3Context* error))complete;
/**
1.关闭数据库上下文操作
2.调用此方法之后 这个context对象将不再有效 如果需要使用,需要在ssqliteManager中的类方法再次返回
*/
- (void)closeContext;
/*
异常提示信息
*/
@property (nonatomic, strong) NSString* errorInfo;
/*
异常对应的code 码
*/
@property (nonatomic, assign) NSInteger errorCode;
@end
#import "Sqlite3Context.h"
@implementation Sqlite3Context
- (instancetype)init{
if (self = [super init]) {
} return self;}
#pragma mark-----打开一个数据库 不存在则创建
- (BOOL)openDataBaeWithName:(NSString *)path{
if (sqlite3_open(path.UTF8String, &_sqlite3_db) !=SQLITE_OK) { sqlite3_close(_sqlite3_db);
_sqlite3_db = nil;
return NO; }
else{ return YES;
}}
#pragma mark----在数据库中创建一张表,如果已经存在,则返回错误信息-dic中的key为所创造的表的参数名;value为修饰条件- (void)createTableWithName:(NSString *)name keysDictionary:(NSDictionary*)dic callBack:(void (^)(Sqlite3Context *))complete{
NSMutableString * keys = [[NSMutableString alloc]init];
for (int i=0; i< dic.allKeys.count;i++){
NSString * key = dic.allKeys[i];
NSLog(@"%@",key);
if (i<dic.allKeys.count-1){
[keys appendFormat:@"%@ %@,",key,[dic objectForKey:key]];
}else{
[keys appendFormat:@"%@ %@",key,[dic objectForKey:key]];
}
}
NSString* sqlStr = [NSString stringWithFormat:@"create table %@(%@)",name,keys];
NSLog(@"%@",sqlStr);
[self runSQL:sqlStr callBack:^(Sqlite3Context *error) {
if (complete) {
complete(error);
}
}];
}
#pragma mark---插入数据
- (void)insertData:(NSDictionary*)dataDict intoTable:(NSString *)name callBack:(void (^)(Sqlite3Context *))complete{
NSMutableString* keys = [[NSMutableString alloc]init];
NSMutableString* values = [[NSMutableString alloc]init];
for (NSInteger index =dataDict.allKeys.count-1; index>=0; index--) {
NSString* key1 = dataDict.allKeys[index];
if (index <= dataDict.allKeys.count-1) {
if (index >0) {
[keys appendFormat:@"%@,",key1];
[values appendFormat:@"\"%@\",",[dataDict objectForKey:key1]];
}else if (index == 0){
[keys appendFormat:@"%@",key1];
[values appendFormat:@"\"%@\"",[dataDict objectForKey:key1]];
} } }
NSString* sqlStr = [NSString stringWithFormat:@"insert into %@(%@) values(%@)",name,keys,values];
[self runSQL:sqlStr callBack:^(Sqlite3Context *error) {
if (complete) { complete(error);
} }];}
#pragma mark-----向表中添加一个键
- (void)addKey:(NSString *)keyName keyType:(NSString *)type intoTable:(NSString *)tableName callBack:(void (^)(Sqlite3Context *))complete{
NSString* sqlStr = [NSString stringWithFormat:@"alter table %@ add %@ %@",tableName,keyName,type];
[self runSQL:sqlStr callBack:^(Sqlite3Context *error) {
if (complete) {
complete(error);
} }];}
#pragma mark----修改数据--whileStr 为空即可
- (void)update:(NSDictionary*)dataDict inTable:(NSString *)tableName whileString:(NSString *)whileStr callBack:(void (^)(Sqlite3Context *))complete{ NSMutableString* sqlStr = [[NSMutableString alloc]init];
[sqlStr appendFormat:@"update %@ set ",tableName];
for (int index = 0; index < dataDict.allKeys.count; index++) {
NSString* key = dataDict.allKeys[index];
if (index < dataDict.allKeys.count - 1) {
[sqlStr appendFormat:@"%@=\"%@\",",key,[dataDict objectForKey:key]];
}
else{ [sqlStr appendFormat:@"%@=\"%@\"",key,[dataDict objectForKey:key]];
if (whileStr != nil) {
[sqlStr appendFormat:@" where %@",whileStr];
} } }
[self runSQL:sqlStr callBack:^(Sqlite3Context *error) { if (complete) { complete(error);
} }];}
#pragma mark---删除数据
- (void)deleteDataFromTable:(NSString *)tableName whereString:(NSString *)whileStr callBack:(void (^)(Sqlite3Context *))complete{
NSMutableString* sqlStr = [[NSMutableString alloc]init];
[sqlStr appendFormat:@"delete from %@",tableName]; if (whileStr != nil) {
[sqlStr appendFormat:@" where %@",whileStr]; }
[self runSQL:sqlStr callBack:^(Sqlite3Context *error) {
if (complete) {
complete(error);
} }];}
#pragma mark----删除一张表
- (void)dropTable:(NSString *)tableName callBack:(void (^)(Sqlite3Context *))complete{ NSString* sqlStr = [NSString stringWithFormat:@"drop table %@",tableName]; [self runSQL:sqlStr callBack:^(Sqlite3Context *error) {
if (complete) {
complete(error);
} }];}
#pragma mark---查询数据
- (void)selectKeys:(NSArray*)keys fromTable:(NSString *)tableName orderBy:(NSString *)orderKey orderType:(NSString *)type whileStr:(NSString *)whileStr callBack:(void (^)(NSArray*, Sqlite3Context *))complete{
NSMutableString* sqlStr = [[NSMutableString alloc]init];
[sqlStr appendFormat:@"select"];
if (keys==nil || keys.count ==0) {
[sqlStr appendFormat:@" * from %@",tableName];
}
else{
for (int index = 0; index < keys.count; index++) {
if (index < keys.count-1) {
[sqlStr appendFormat:@" %@,",keys[index].allKeys.firstObject]; }
else{
[sqlStr appendFormat:@" %@ from %@",keys[index].allKeys.firstObject,tableName];
} } }
if (whileStr) {
[sqlStr appendFormat:@" where %@",whileStr];
}
if (orderKey) {
[sqlStr appendFormat:@" order by %@",orderKey]; }
if (type) {
[sqlStr appendFormat:@" %@",type];
}
NSMutableArray* keysArr = [[NSMutableArray alloc]init];
NSMutableArray* keysTypeArr = [[NSMutableArray alloc]init];
if (keys==nil ||keys.count == 0) {
NSArray* tmpArr = [self getTheTableAllKeys:tableName]; for (int index = 0; index < tmpArr.count; index++) {
NSString* key = tmpArr[index].allKeys.firstObject;
[keysArr addObject:key];
[keysTypeArr addObject:[tmpArr[index] objectForKey:key]];
}
}else{
for (int index = 0; index < keys.count; index++) {
NSString* key = keys[index].allKeys.firstObject;
[keysArr addObject:key];
[keysTypeArr addObject:[keys[index] objectForKey:key]];
} }
[self runSelectSQl:sqlStr withKeys:keysArr withDataType:keysTypeArr callBack:^(NSArray*dataArray, Sqlite3Context *error) {
if (complete) {
complete(dataArray,error);
} }];}
#pragma mark------关闭数据库上下文操作- (void)closeContext{ sqlite3_close(_sqlite3_db);
_sqlite3_db = nil;
}
#pragma mark----内部方法-运行创建独立的非查询Sqlite语句
- (void)runSQL:(NSString *)sql callBack:(void(^)(Sqlite3Context* error))complete{
char* error;
int code = sqlite3_exec(_sqlite3_db,sql.UTF8String, NULL, NULL, &error);
if (code != SQLITE_OK) {
Sqlite3Context* err = [[Sqlite3Context alloc]init];
err.errorInfo = [NSString stringWithCString:error encoding:NSUTF8StringEncoding]; err.errorCode = code;
complete(err); }
else{
complete(nil);
}}
#pragma mark----运行查询语句
- (void)runSelectSQl:(NSString *)sql withKeys:(NSArray *)keys withDataType:(NSArray *)dataTYpe callBack:(void (^)(NSArray* dataArray,Sqlite3Context* error))complete{
sqlite3_stmt* stmt = nil;
int code = sqlite3_prepare_v2(_sqlite3_db, sql.UTF8String, -1, &stmt, NULL);
if (code != SQLITE_OK) {
Sqlite3Context* error = [[Sqlite3Context alloc]init];
error.errorInfo = @"查询失败";
error.errorCode = code;
complete(nil,error);
}else{
NSMutableArray* resultArr = [[NSMutableArray alloc]init];
while (sqlite3_step(stmt) == SQLITE_ROW) {
//数据类型的分别解析
NSMutableDictionary* dic = [[NSMutableDictionary alloc]init];
for (int i = 0; i < dataTYpe.count; i++) {
NSString* type = dataTYpe[i];
if ([type isEqualToString:YHBASE_SQL_DATATYPE_BINARY]) {//二进制
int length = sqlite3_column_bytes(stmt, i);
const void* data = sqlite3_column_blob(stmt, i);
NSData* value = [NSData dataWithBytes:data length:length];
[dic setObject:value forKey:keys[i]];
}else if ([type isEqualToString:YHBASE_SQL_DATATYPE_BLOB]){
int length = sqlite3_column_bytes(stmt, i);
const void* data = sqlite3_column_blob(stmt, i);
NSData* value = [NSData dataWithBytes:data length:length];
[dic setObject:value forKey:keys[i]];
}else if ([type isEqualToString:YHBASE_SQL_DATATYPE_BOOLEAN]){
NSNumber* value = [NSNumber numberWithInt:sqlite3_column_int(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if ([type isEqualToString:YHBASE_SQL_DATATYPE_CURRENCY]){
NSNumber* value = [NSNumber numberWithLong:sqlite3_column_int64(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if ([type isEqualToString:YHBASE_SQL_DATATYPE_DATE]){
char * cString =(char*)sqlite3_column_text(stmt, i);
NSString * value = [NSString stringWithCString:cString?cString:"NULL" encoding:NSUTF8StringEncoding];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_DOUBLE]){
NSNumber * value = [NSNumber numberWithFloat:sqlite3_column_double(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_FLOAT]){
NSNumber * value = [NSNumber numberWithFloat:sqlite3_column_double(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_INTRGER]){
NSNumber * value = [NSNumber numberWithInt:sqlite3_column_int(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_REAL]){
NSNumber * value = [NSNumber numberWithDouble:sqlite3_column_int(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_SMALLINT]){
NSNumber * value = [NSNumber numberWithShort:sqlite3_column_int(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_TEXT]){
char * cString =(char*)sqlite3_column_text(stmt, i);
NSString * value = [NSString stringWithCString:cString?cString:"NULL" encoding:NSUTF8StringEncoding];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_TIME]){
char * cString =(char*)sqlite3_column_text(stmt, i);
NSString * value = [NSString stringWithCString:cString?cString:"NULL" encoding:NSUTF8StringEncoding];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_TIMESTAMP]){
NSNumber * value = [NSNumber numberWithLongLong:sqlite3_column_int64(stmt, i)];
[dic setObject:value forKey:keys[i]];
}else if([type isEqualToString:YHBASE_SQL_DATATYPE_VARCHAR]){
char * cString =(char*)sqlite3_column_text(stmt, i);
NSString * value = [NSString stringWithCString:cString?cString:"NULL" encoding:NSUTF8StringEncoding];
[dic setObject:value forKey:keys[i]];
}
}
[resultArr addObject:dic];
}
sqlite3_finalize(stmt);//销毁stmt,回收资源
stmt=nil;
complete(resultArr,nil);
}
}
调用方法:
- (void)createTable:(id)tag{
Sqlite3Context* context = [[Sqlite3Context alloc]init];
NSString* path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject] stringByAppendingPathComponent:@"zhaobin.db"];
NSLog(@"%@",path);
if ([context openDataBaeWithName:path]) {
[context createTableWithName:@"love" keysDictionary:@{@"name":@"text",@"age":@"text"} callBack:^(Sqlite3Context *error) {
}];
}
[context closeContext];
}
- (void)InsertData:(id)tag{
Sqlite3Context* context = [[Sqlite3Context alloc]init];
NSString* path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject] stringByAppendingPathComponent:@"zhaobin.db"];
if ([context openDataBaeWithName:path]) {
[context insertData:@{@"name":@"wenwen",@"age":@"25"} intoTable:@"love" callBack:^(Sqlite3Context *error) {
}];
}
[context closeContext];
}
- (void)updateData:(id)tag{
Sqlite3Context* context = [[Sqlite3Context alloc]init];
NSString* path = [[NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) firstObject] stringByAppendingPathComponent:@"zhaobin.db"];
if ([context openDataBaeWithName:path]) {
[context update:@{@"name":@"leilei"} inTable:@"love" whileString:nil callBack:^(Sqlite3Context *error) {
}];
}
[context closeContext];
}