LOBS, BLOBS, CLOBS Dealing with Attachments in APEX

Transcription

1 LOBS, BLOBS, CLOBS Dealing with Attachments in APEX Tim St. Hilaire June 2013

2 The Plan Intro The Goal APEX BLOB Wizard Making It Your Own Base Technology Advanced Database Concepts QuesGons

3 IntroducGon Tim St. Hilaire System Integrator Problems Solver PragmaGst Technology Enthusiast APEX Fan Enkitec Product Developer

4 The Goal Ability to accept file anachment input from users in an applicagon Use the content in applicagons either as text, images, or downloadable to users Understand how the data is stored, retrieved, and managed inside the database

5 DemonstraGon The wphilltech.com

6 @sthilaire wphilltech.com The Academics

7 The Academics LOB Large Objects broken down into datatypes BLOB - Stores unstructured binary data in the database as a bit stream CLOB Stores large amounts of text such as XML in the database character set NCLOB NaGonal Character Set LOB stores Unicode data BFILE external LOB Secure File LOB file data enabling advanced features such as compression and encrypgon

8 BLOB vs. CLOB BLOB Stream of data intended to be binary Chunks are returned in RAW format (substr) CLOB Will translate between character sets Chunks are returned in VARCHAR2 format (substr) SELECT * FROM NLS_DATABASE_PARAMETERS WHERE PARAMETER = 'NLS_CHARACTERSET';

9 There are 10 types of people in the world Those that understand binary, and those that don t. - - The Internet

10 wphilltech.com

11 DemonstraGon - APEX Submit BuNon

12 Where did the file go? WWV_FLOW_FILES APEX_APPLICATION_FILES

13 Table Context SensiGvity APEX_APPLICATION_FILES limits to files available in the worksapce. Includes applicagons that were uploaded by all applicagons Includes files that have been uploaded via the builder Includes StaGc Shared Component Files for the ApplicaGon and the Workspace

14 Evaluate WWV_FLOW_FILES Pros No Table CreaGons Required Consistent ImplementaGon Storage in a known locagon Cons Need Remote Key Storage ApplicaGon Files combined Storage for all Workspaces is shared

15 Custom wphilltech.com

16 My Table To configure your own table Minimum Requirements Adjust to Features and Business Requirements BLOB_ID NUMBER (your choice) ACTUAL_FILE BLOB FILE_NAME VARCHAR2 MIMETYPE VARCHAR2

17 Custom Table CREATE TABLE MY_APEX_FILES ( BLOB_ID NUMBER, NAME VARCHAR2(100 BYTE), DESCRIPTION VARCHAR2(2000 BYTE), BLOB_CONTENT BLOB, BLOB_SIZE NUMBER, MIME_TYPE VARCHAR2(255 BYTE), FILE_NAME VARCHAR2(255 BYTE), CREATED_BY VARCHAR2(50 BYTE), CREATED_ON DATE, UPDATED_BY VARCHAR2(50 BYTE), UPDATED_ON DATE );

18 wphilltech.com

19 File Browse wphilltech.com

20 Display wphilltech.com

21 Display wphilltech.com

22 Display wphilltech.com

23 Display wphilltech.com

24 Showing Contents in a Report

25 Notes From the Field The Report column is NOT the BLOB content The Report column is calculated as SIZE The MIME_TYPE is important for usability

26 Report Content = wphilltech.com

27 Notes From the Field The report column containing the primary key must be named the same as the primary key field in the BLOB table even if the BLOB table is not in the report Fields are ignored based on format selecgons (inline vs. download)

28 Report - Include wphilltech.com

29 Link CreaGon Result <a href="apex_ugl.get_blob? s= &a=500&c= &p=200&k1= &k2=&ck=BD47E34C8E5A ECD457A4574B4&rt=IR" alt="download" Gtle="Download 58KB">Download</a>

30 Notes From the Field Case SensiGve Names Apex_applicaGon_files!= APEX_APPLICATION_FILES

31 Report - Include Image As a Column in a Select Statement: CASE WHEN MIME_TYPE LIKE 'image%' THEN '<img src="' apex_util.get_blob_file_src( 'P210_BLOB_CONTENT',ID) '" height="75" width="75" /> ELSE NULL END as shrunk

32 @sthilaire wphilltech.com Text

33 Quiz What is the size limit of a VARCHAR2? (A) 255 (B) 2000 (C) 4000 (D) (E) 8 Terabytes (F) Whatever it is defined as.

34 Maximum wphilltech.com

35 Rich Text Editor Character Limit! Or The most descripgve error messages ever

36 DemonstraGon Text Region Error

37 Plugin Rich wphilltech.com

38 DemonstraGon Text Region Plugin

39 @sthilaire wphilltech.com The Next Level of Complexity

40 Once Upon a Tablespace_apex tablespace_files tablespace_temp SYSAUX SYSAUX TEMP /i/

41 Specify LOB Storage LocaGon CREATE TABLE ContainsLOB_tab ( n NUMBER, c CLOB) lob (c) STORE AS BASICFILE segname (TABLESPACE lobtbs1 CHUNK 4096 PCTVERSION 5 NOCACHE LOGGING STORAGE (MAXEXTENTS 5) );

42 Size of Tables SELECT l.table_name '-lob', s.bytes FROM user_lobs l, user_segments s WHERE s.segment_name = l.segment_name AND s.segment_type = 'LOBSEGMENT'

43 Size MaNers ALTER TABLE MY_TABLE DEALLOCATE UNUSED; ALTER TABLE MY_TABLE enable ROW MOVEMENT; ALTER TABLE MY_TABLE SHRINK SPACE cascade; ALTER TABLE MY_TABLE disable ROW MOVEMENT; Find a DBA to Partner With

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45 QuesGons and wphilltech.com

46 References Many thanks to all those that have come before me, and for those that take the Gme to help others grow and improve their skills by sharing their Gme an knowledge. APEX Docs BLOB in APEX hnp://docs.oracle.com/cd/e37097_01/doc/doc.42/e35125/advnc_blob.htm#htmdb25906 GET_BLOB_FILE_SRC hnp://docs.oracle.com/cd/e37097_01/doc/doc.42/e35127/apex_ugl.htm#aeapi129 DBMS_LOB hnp://docs.oracle.com/cd/e11882_01/appdev.112/e25788/d_lob.htm Oracle SecureFiles and Large Objects hnp://docs.oracle.com/cd/e11882_01/appdev.112/e18294/adlob_tables.htm hnp://docs.oracle.com/cd/e11882_01/appdev.112/e18294/adlob_lob_ops.htm APEX Builder - BLOB Support in Forms and Reports hnp://docs.oracle.com/cd/e37097_01/doc/doc.42/e35125/advnc_blob.htm Icons hnp://

47 Disclaimer Marks, images, brands and referenced content are the property of their respecgve owners. Usage is for discussion purposes only. No ownership assumed or implied. The comments and opinions expressed here are sole responsibility of the author and not of his employer or any other party. No trees were harmed during the creagon of this presentagon. However, a great number of electrons were terribly inconvenienced.