ibm-information-center/dist/eclipse/plugins/i5OS.ic.sqlp_5.4.0.1/rbafydisplaylobcol.htm

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<h1 class="topictitle1">Display layout of LOB columns</h1>
<div><p>When a row of data from a table holding LOB columns is displayed
using CL commands such as Display Physical File Member (DSPPFM), the LOB
data stored in that row will not be displayed. Instead, the database shows
a special value for the LOB columns.</p>
<div class="section"><p>The layout of this special value is as follows:</p>
<ul><li>13 to 28 bytes of hexadecimal zeros.</li>
<li>16 bytes beginning with *POINTER and followed by blanks.</li>
</ul>
<p>The number of bytes in the first portion of the value is set to the
number needed to 16 byte boundary align the second part of the value.</p>
</div>
<div class="section"><p>For example, say you have a table that holds three columns: ColumnOne
Char(10), ColumnTwo CLOB(40K), and ColumnThree BLOB(10M). If you were to
issue a DSPPFM of this table, each row of data looks as follows.</p>
<ul><li>For ColumnOne: 10 bytes filled with character data.</li>
<li>For ColumnTwo: 22 bytes filled with hexadecimal zeros and
16 bytes filled with '*POINTER '.</li>
<li>For ColumnThree: 16 bytes filled with hexadecimal zeros and 16 bytes
filled with '*POINTER '.</li>
</ul>
<p>The full set of commands that display LOB columns in this way is:</p>
<ul><li>Display Physical File Member (DSPPFM)</li>
<li>Copy File (CPYF) when the value *PRINT is specified for the TOFILE keyword</li>
<li>Display Journal (DSPJRN)</li>
<li>Retrieve Journal Entry (RTVJRNE)</li>
<li>Receive Journal Entry (RCVJRNE) when the values *TYPE1, *TYPE2, *TYPE3
and *TYPE4 are specified for the ENTFMT keyword.</li>
</ul>
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<div class="familylinks">
<div class="parentlink"><strong>Parent topic:</strong> <a href="rbafylobs.htm" title="The VARCHAR, VARGRAPHIC, and VARBINARY data types have a limit of 32 KB (where KB equals 1024 bytes) of storage. While this may be sufficient for small to medium-size text data, applications often need to store large text documents. They might also need to store a wide variety of additional data types such as audio, video, drawings, mixed text and graphics, and images. There are three data types to store these data objects as strings of up to 2 GB (where GB equals 1 073 741 824 bytes).">Use large objects (LOBs)</a></div>
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