DBCDatabaseResult

#DBCDatabaseResult Class Reference
[SQLitews]:http://www.sqlite.org
[APPLFastEnumerationProtocol]:http://developer.apple.com/library/ios/#documentation/cocoa/reference/NSFastEnumeration_protocol/Reference/NSFastEnumeration.html [DBCDatabaseRowCR]:https://github.com/parfeon/DBConnect/wiki/DBCDatabaseRow
[DBCDatabaseCR]:https://github.com/parfeon/DBConnect/wiki/DBCDatabase
[DBCDatabaseBasicExample]:https://github.com/parfeon/DBConnect/wiki/DBCDatabase#basicExample
[DBCDatabaseExecuteQuery]:https://github.com/parfeon/DBConnect/wiki/DBCDatabase#m12
Overview
This class holds all information retrieved from query execution with [executeQuery:error:][DBCDatabaseExecuteQuery].
This class holds information about:

• column names
• SQL query, which was used
• rows with data
• count of rows with data

This class implements [NSFastEnumeration protocol][APPLFastEnumerationProtocol] so it can be easily used in `for..in` cycles.

##Tasks
###DBCDatabaseResult initialization
+ resultWithPreparedStatement:encoding:
- initWidthPreparedSatetement:encoding:
###DBCDatabaseResult rows manipulation
- addRowFromStatement:
- rowAtIndex:
###DBCDatabaseResult properties
count
columnNames
queryExecutionDuration
query

##Properties

count

This property stores count of [DBCDatabaseRow][DBCDatabaseRowCR] instance entries.

@property (nonatomic, readonly)int count

Discussion
This parameter stores information about how many rows were retrieved from last query.

How to use
In this example, we will use results from one of the [examples][DBCDatabaseBasicExample], shown earlier in [DBCDatabase Class Reference][DBCDatabaseCR] and retrieve rows count:

error = nil;
DBCDatabaseResult *result = [db executeQuery:@"SELECT * FROM test" error:&error, nil];
if(error == nil){
    int rowsCount = [result count];
    NSLog(@"Rows count: %i", rowsCount);
} else {
    // In some rare cases an error may occur, just log it out to find out what was wrong. Or you can set a flag
       for DBCUseDebugLogger in DBCConfiguration.h, than DBConnect will log out all debug information.  
    NSLog(@"Occurred an error: %@", error);
}

/* Output:
    Rows count: 4
*/

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---

columnNames

This property stores column names from recent SQL statement.

@property (nonatomic, readonly, getter = columnNames)NSArray *colNames

Discussion
This parameter stores a list of columns' names.

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---

queryExecutionDuration

This property stores duration of SQL query statement execution.

@property (nonatomic, assign)NSTimeInterval queryExecutionDuration

Discussion
If DBCShouldProfileQuery enabled in DBCConfiguration.h, than this parameter will store time, which was spent for query execution.

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---

query

This property stores SQL statement for recent query execution.

@property (nonatomic, readonly, getter = query)NSString *querySQL

Discussion
This property stores SQL query statement, which was used for last query execution.

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##Class methods

resultWithPreparedStatement:encoding:

Create and initialize DBCDatabaseResult instance with specified SQL statement and encoding.

+ (id)resultWithPreparedStatement:(sqlite3_stmt*)statement encoding:(DBCDatabaseEncoding)databaseEncoding

Parameters
statement
    [SQLite][SQLitews] statement, used for query.
databaseEncoding
    current encoding, used for opened database connection.

Return value
Autoreleased DBCDatabaseResult instance.

Discussion
This method creates and initializes DBCDatabaseResult instance, which is ready to use by DBCDatabase.

See Also
- initWidthPreparedSatetement:encoding:

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##Instance methods

initWidthPreparedSatetement:encoding:

Initialize DBCDatabaseResult instance with specified SQL statement and encoding.

- (id)initWidthPreparedSatetement:(sqlite3_stmt*)statement encoding:(DBCDatabaseEncoding)databaseEncoding

Parameters
statement
    [SQLite][SQLitews] statement, used for query.
databaseEncoding
    current encoding, used for opened database connection.

Return value
Initialized DBCDatabaseResult instance.

Discussion
This method initialize DBCDatabaseResult instance, which is ready to use by DBCDatabase.

See Also
+ resultWithPreparedStatement:encoding:

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