FMDatabase 的使用方法

FMDatabase

的使用方法

FMDatabase

的使用方法

- (NSString*) getPath {

NSArray* paths

=NSSearchPath ForDirectoriesInDomains(NSDocumentDirector

< br>y,NSUserDomainMask, YES)

return

[[pathsob jectAtIndex:0]stringByAppendingPathComponent:@

MyTable

１

.

创 建数据库

-(void)CreateTable;{dataBase =

[FMDatabasedatabaseWithPath:[selfgetPath]];

if

(![dataBase open])

NSLog(@

}

[dataBaseexecut eUpdate:@

MyTable(aa float,bb text,cc integer,dd integer,ee text)

[dataBaseclose];}

２

.

查询数据

-(void)Que ryData{//

获取数据

recordArray = [[NSMutableArrayalloc]init];

db =

[[FMDatabas ealloc]initWithPath:[selfgetPath]];

if ([db

open]) {

FMResultSet *rs =

[dbexecuteQuery:@

while ([rs next]){

OneRecord = [[OneRecord

alloc]init];

=

[NSNumbernumberWithFloat:[rs doubleForColumn:@

= [rs stringForColumn:@

= [NSNumbernumberWithInt:[rs

intForColumn:@

=

[NSNumbernumberWithInt:[rs intForColumn:@

= [rs stringForColumn:@

[recordArrayaddObject: OneRecord];

[OneRecordrelease];

}

[rs close];

[dbclose];}

３

.

更新数据

-(void)UpdateData{if ([dbopen])

{

[dbbeginTransaction];

[dbexecuteUpdate:@

date = ?

[dbexecuteUpdate:@

MyTable SET bb = ? WHERE date = ?

[dbexecuteUpdate:@

date = ?

[dbexecuteUpdate:@

MyTable SET dd = ? WHERE date = ?

[dbcommit];

db close];

}

}

４。插入数据

-(void)insertData{//

插入数据库

[dbbeginTransaction];

[dbexecuteUpdate:@

MyTable (aa,bb,cc,dd,ee) V

ALUES (?,?,?,?,?)

NSNumber

numberWithFloat:aa],bb,cc,dd,ee];

db commit];

db

close];

}

５。官方的使用方法为：

UsageThere are three main classes in FMDB:FMDatabase -

Represents a single SQLite database. Used for executing SQL

ltSet - Represents the results of executing a

query on baseQueue - If you're wanting

to perform queries and updates on multiple threads, you'll want

to use this class. It's described in the

se CreationAn FMDatabase is created with a path

to a SQLite database file. This path can be one of these three:A

file system path. The file does not have to exist on disk. If it

does not exist, it is created for empty string (@

empty database is created at a temporary location. This database

is deleted with theFMDatabase connection is . An

in-memory database is created. This database will be destroyed

with theFMDatabase connection is closed.(For more

information on temporary and in-memory databases, read the

sqlite documentation on the

subject:/)FMDatabase

*db = [FMDatabase

databaseWithPath:@

interact with the database, it must be opened. Opening fails if

there are insufficient resources or permissions to open and/or

create the (![db open]) {

[db release];

return;}Executing UpdatesAny sort of SQL statement which is

not a SELECT statement qualifies as an update. This includes

CREATE, PRAGMA,UPDATE, INSERT, ALTER,COMMIT,

BEGIN, DETACH,DELETE, DROP, END,EXPLAIN,

V

ACUUM, and REPLACE statements (plus many more).

Basically, if your SQL statement does not begin withSELECT, it

is an update ing updates returns a single value,

a BOOL. A return value of YES means the update was

successfully executed, and a return value of NO means that

some error was encountered. If you use the -[FMDatabase

executeUpdate:error:withArgumentsInArray:orV