6
Frequently Asked Questions

This chapter includes the following Frequently Asked Questions (FAQs):

• Converting Data Types to LOB Data Types
  • Can I Insert or Update Any Length Data Into a LOB Column?

  • Does COPY LONG to LOB Work if Data is > 64K?

• General
  • How Do I Determine if the LOB Column with a Trigger is Being Updated?

  • Reading and Loading LOB Data: What Should Amount Parameter Size Be?

• Index-Organized Tables (IOTs) and LOBs
  • Is Inline Storage Allowed for LOBs in Index-Organized Tables?

• Initializing LOB Locators
  • When Do I Use EMPTY_BLOB() and EMPTY_CLOB()?

  • How Do I Initialize a BLOB Attribute Using EMPTY_BLOB() in Java?

• JDBC, JPublisher and LOBs
  • How Do I Insert a Row With Empty LOB Locator into Table Using JDBC?

  • JDBC: Do OracleBlob and OracleClob Work in 8.1.x?

  • How Do I Manipulate LOBs With the 8.1.5 JDBC Thin Driver?

  • Is the FOR UPDATE Clause Needed on SELECT When Writing to a LOB?

• Loading LOBs and Data Into LOBs
  • How do I Load a 1Mb File into a CLOB Column?

  • How Do We Improve BLOB and CLOB Performance When Using JDBC Driver To Load?

• LOB Indexing
  • Is LOB Index Created in Same Tablespace as LOB Data?

  • Indexing: Why is a BLOB Column Removed on DELETing but not a BFILE Column?

  • Which Views Can I Query to Find Out About a LOB Index?

• LOB Storage and Space Issues
  • What Happens If I Specify LOB Tablespace and ENABLE STORAGE IN ROW?

  • What Are the Pros and Cons of Storing Images in a BFILE Versus a BLOB?

  • When Should I Specify DISABLE STORAGE IN ROW?

  • Do <4K BLOBs Go Into the Same Segment as Table Data, >4K BLOBs Go Into a Specified Segment?

  • Is 4K LOB Stored Inline?

  • How is a LOB Locator Stored If the LOB Column is EMPTY_CLOB() or EMPTY_BLOB() Instead of NULL? Are Extra Data Blocks Used For This?

• Migrating From Other Database Systems
  • Is Implicit LOB Conversion Between Different LOB Types Allowed in Oracle8i?

• Performance
  • What Can We Do To Improve the Poor LOB Loading Performance When Using Veritas File System on Disk Arrays, UNIX, and Oracle?

  • Is There a Difference in Performance When Using DBMS_LOB.SUBSTR Versus DBMS_LOB.READ?

  • Are There Any White Papers or Guidelines on Tuning LOB Performance?

  • When Should I Use Chunks Over Reading the Whole Thing?

  • Is Inlining the LOB a Good Idea and If So When?

  • Are There Any White Papers or Guidelines on Tuning LOB Performance?

  • How Can I Store LOBs >4Gb in the Database?