7 Nokia Corporation - initial contribution. |
7 Nokia Corporation - initial contribution. |
8 Contributors: |
8 Contributors: |
9 --> |
9 --> |
10 <!DOCTYPE concept |
10 <!DOCTYPE concept |
11 PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd"> |
11 PUBLIC "-//OASIS//DTD DITA Concept//EN" "concept.dtd"> |
12 <concept xml:lang="en" id="GUID-EFA822E0-BE80-5EB8-82E5-1659BDB1BDD9"><title>Named database</title><prolog><metadata><keywords/></metadata></prolog><conbody><p>In order to support the DBMS client-server interface, the <codeph>RDbNamedDatabase</codeph> class provides the interface for creating and opening databases identified by name.</p> <p>The mechanism is generic; the database is identified by its name and the database format. The format is a name that is used to identify the implementation used for creating or opening that database. There is a default format, which has the name "epoc". The default format is a store database in the root stream of the database file.</p> <p>If required, other formats can be provided in extension DBMS driver libraries. These formats need no be file-based. Additional DBMS driver libraries are dynamically bound to the API at run-time, if one can be found to support the format requested.</p> <p>Formats which are UidTyped files, such as the default, can allow the client to specify a 3rd Uid by extending the format name with the Uid name (as generated by the <codeph>Name()</codeph> member function of <codeph>TUid</codeph>, an 8 digit hexadecimal number enclosed in square brackets).</p> <p>If specified, this is also checked when a database is opened. e.g. creating a FileStore database “C:\My Database” with a 3rd Uid of 0x10001234:</p> <codeblock id="GUID-2291B3E7-D3D5-5E99-8ACA-886163557978" xml:space="preserve">_LIT(KMydatabase,"C:\\My Database"); |
12 <concept id="GUID-EFA822E0-BE80-5EB8-82E5-1659BDB1BDD9" xml:lang="en"><title>Named |
|
13 database</title><shortdesc>Describes how databases can be created and opened using the database |
|
14 name.</shortdesc><prolog><metadata><keywords/></metadata></prolog><conbody> |
|
15 <p>In order to support the DBMS client-server interface, the <codeph>RDbNamedDatabase</codeph> class |
|
16 provides the interface for creating and opening databases identified by name.</p> |
|
17 <p>The mechanism is generic; the database is identified by its name and the |
|
18 database format. The format is a name that is used to identify the implementation |
|
19 used for creating or opening that database. There is a default format, which |
|
20 has the name "epoc". The default format is a store database in the root stream |
|
21 of the database file.</p> |
|
22 <p>If required, other formats can be provided in extension DBMS driver libraries. |
|
23 These formats need no be file-based. Additional DBMS driver libraries are |
|
24 dynamically bound to the API at run-time, if one can be found to support the |
|
25 format requested.</p> |
|
26 <p>Formats which are UidTyped files, such as the default, can allow the client |
|
27 to specify a 3rd Uid by extending the format name with the Uid name (as generated |
|
28 by the <codeph>Name()</codeph> member function of <codeph>TUid</codeph>, an |
|
29 8 digit hexadecimal number enclosed in square brackets).</p> |
|
30 <p>If specified, this is also checked when a database is opened. e.g. creating |
|
31 a FileStore database “C:\My Database” with a 3rd Uid of 0x10001234:</p> |
|
32 <codeblock id="GUID-2291B3E7-D3D5-5E99-8ACA-886163557978" xml:space="preserve">_LIT(KMydatabase,"C:\\My Database"); |
13 _LIT(KDemoUid,"[10001234]"); |
33 _LIT(KDemoUid,"[10001234]"); |
14 RDbNamedDatabase database; |
34 RDbNamedDatabase database; |
15 TInt r=database.Create(fs,KMydatabase,KDemoUid);</codeblock> <p>For comparison, the equivalent code required to create an <codeph>RDbStoreDatabase</codeph> in the root of a <codeph>CPermanentFileStore</codeph> would have been:</p> <codeblock id="GUID-B103A01B-55C0-50B5-81F7-F2763E5E16DB" xml:space="preserve">_LIT(KMydatabase,"C:\\My Database"); |
35 TInt r=database.Create(fs,KMydatabase,KDemoUid);</codeblock> |
|
36 <p>For comparison, the equivalent code required to create an <codeph>RDbStoreDatabase</codeph> in |
|
37 the root of a <codeph>CPermanentFileStore</codeph> would have been:</p> |
|
38 <codeblock id="GUID-B103A01B-55C0-50B5-81F7-F2763E5E16DB" xml:space="preserve">_LIT(KMydatabase,"C:\\My Database"); |
16 CFileStore* fstore=CPermanentFileStore::ReplaceLC(fs,KMydatabase,EFileWrite); |
39 CFileStore* fstore=CPermanentFileStore::ReplaceLC(fs,KMydatabase,EFileWrite); |
17 fstore->SetTypeL(TUidType(fstore->Layout(),KDatabaseUid,TUid::Uid(0x10001234))); |
40 fstore->SetTypeL(TUidType(fstore->Layout(),KDatabaseUid,TUid::Uid(0x10001234))); |
18 RDbStoreDatabase database; |
41 RDbStoreDatabase database; |
19 fstore->SetRootL(database.CreateL(fstore)); |
42 fstore->SetRootL(database.CreateL(fstore)); |
20 fstore->CommitL();</codeblock> <p>A named database may be encrypted; the default is an un-encrypted database.</p> </conbody></concept> |
43 fstore->CommitL();</codeblock> |
|
44 <p>A named database may be encrypted; the default is an un-encrypted database.</p> |
|
45 </conbody></concept> |