FILELOAD command: Difference between revisions
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<dd>Starts a File Load (single-step) program | <dd>Starts a File Load (single-step) program | ||
</dl> | </dl> | ||
==Syntax== | ==Syntax== | ||
<p class="syntax">FILELOAD <i>k</i>, <i>n</i>, <i>m</i> [,[<i>s1</i>] [,[<i>s2</i>] [,[<i>s3</i>] [,[<i>s4</i>] | <p class="syntax">FILELOAD <i>k</i>, <i>n</i>, <i>m</i> [,[<i>s1</i>] [,[<i>s2</i>] [,[<i>s3</i>] [,[<i>s4</i>] [,v1]]]]] | ||
</p> | </p> | ||
Where: | |||
<table> | <table> | ||
<tr> | <tr> | ||
<th>k </th> | <th>k </th> | ||
<td> | <td>The maximum number of records to be loaded into the <var class="product">Model 204</var> file.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>n</th> | <th>n</th> | ||
<td> | <td>The maximum number of times that the statements in the File Load program are to be executed.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>m</th> | <th>m</th> | ||
<td> | <td>The number of input records to skip before starting the load process.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>s1</th> | <th>s1</th> | ||
<td> | <td>The amount of memory that the sort uses for sorting the deferred update index records produced by the File Load program. If <var class="term">s1</var> is omitted or is not a positive integer, a default value of 50000 bytes (64K for z/VM) is used for the sort work space. | ||
<p>It is important to increase <var class="term">s1</var> for large sorts. The <var class="term">s1</var> parameter should be made as large as practical, especially for sorts involving many records.</p></td> | |||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>s2</th> | <th>s2</th> | ||
<td> | <td>The amount of memory to be used for sorting the deferred update FRV index records. It defaults to 50000 bytes (64K for z/VM) if <var class="term">s2</var> is omitted or is not a positive integer. For 3380 disk drives, the minimum values for <var class="term">s1</var> and <var class="term">s2</var> are 64000 bytes.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>s3</th> | <th>s3</th> | ||
<td> | <td>The amount of memory to be allocated for the two buffers used to pass data from <var class="product">Model 204</var> to the sorts. This parameter specifies the combined size of the two buffers. The core specified in <var class="term">s3</var> is evenly divided between the two buffers, and <var class="term">s3</var> defaults to 8000 bytes. | ||
<p>The minimum value accepted is 48 bytes, but such a small size is not recommended. Larger sizes might produce a noticeable performance improvement. An increase in <var class="term">s1</var> normally has a greater effect on performance than a corresponding increase in <var class="term">s31</var>.</p></td> | |||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>s4</th> | <th>s4</th> | ||
<td> | <td>The amount of memory that is allocated for the two buffers used to pass data from the sorts to <var class="product">Model 204</var>. <var class="term">s4</var> is ordinarily equal in size to <var class="term">s3</var>, and it is set equal to <var class="term">s3</var> by default.</td> | ||
</tr> | </tr> | ||
<tr> | <tr> | ||
<th>vl</th> | <th>vl</th> | ||
<td> | <td>The maximum sort record length in variable-length record sorts. | ||
<p>The vl parameter is required when ORDERED fields are updated by the File Load program. For efficiency, the vl option should not be present when ORDERED fields are not updated. For more information on | <p>The <var class="term">vl</var> parameter is required when ORDERED fields are updated by the File Load program. For efficiency, the <var class="term">vl</var> option should not be present when ORDERED fields are not updated. For more information on the <var class="term">vl</var> option, | ||
</td> | see [[Deferred update feature#Setting the variable-length sort parameter (vl)|Setting the variable-length sort parameter (vl)]]. </p> | ||
</tr> | </td></tr> | ||
</table> | </table> | ||
===Syntax notes=== | ===Syntax notes=== | ||
FILELOAD must be issued in file context (that is, the current default must be a file, not a group). | <ul> | ||
< | <li><var>FILELOAD</var> must be issued in file context (that is, the current default must be a file, not a group).</li> | ||
<li>Specify commas to hold places for missing arguments. When an argument is missing, the default value (if any) is used. (See the examples below.)</li> | |||
</ul> | |||
==Example== | ==Example== | ||
<p class="code">OPEN CENSUS | <p class="code">OPEN CENSUS | ||
Line 76: | Line 82: | ||
<p class="code">FILELOAD -1, -1, 1,,1000, 1000 | <p class="code">FILELOAD -1, -1, 1,,1000, 1000 | ||
</p> | </p> | ||
==Usage notes== | ==Usage notes== | ||
< | <ul> | ||
< | <li>The <var>FILELOAD</var> command invokes the File Load (FLOD) utility. It is used when a single-step File Load procedure is being performed. | ||
< | <p> | ||
The <var>[[FLOD command|FLOD]]</var> command is used to invoke a multistep File Load procedure. </p> | |||
<p class="note"><b>Note:</b> For a site that is authorized for <var class="product">[[Fast/Reload]]</var>, the <var>FLOD</var> and <var>FILELOAD</var> commands are syntactically unchanged but invoke <var class="product">Fast/Reload</var>, which compiles and executes the <var>FLOD</var> and <var>FILELOAD</var> programs.</p></li> | |||
<li>The <var>FILELOAD</var> command is not supported under z/VSE.</li> | |||
<li><var>FILELOAD</var> signals the start of a File Load program, which consists of special statements that load data from a sequential file into a <var class="product">Model 204</var> file. | |||
<p> | |||
To make the File Load program execute efficiently, set the <var>MAXBUF</var> parameter to a value between 5 and 10. Also, make the value of the <var class="term">s1</var> attribute as large as is practical. The exceptions to these guidelines are:</p> | |||
<ul> | <ul> | ||
<li | <li>FILELOADs of hash-order files that do not use the sort exit M204HASH</li> | ||
</li> | |||
<li | <li>FILELOADs that extensively use the locate statement </li> | ||
</ul></li> | |||
</ | |||
<li>The <var class="product">Model 204</var> <var>FILELOAD</var> exit feature allows for modification of the record image upon which the <var>FILELOAD</var> (or <var>FILELOADX</var>) command acts. With the <var>FILELOAD</var> exit feature, you can create a COBOL or Assembler program to modify the image records. The <var>FILELOAD</var> exit feature enables the use of more than one input file for <var>FILELOAD</var> processing. The <var>FILELOAD</var> exit is modeled on SORT exits, similar to the E15 sort exit. The <var>FILELOAD</var> exit feature is documented in [[FLOD exits]].</li> | |||
< | |||
< | <li>When it processes <var>FILELOAD</var>, <var class="product">Model 204</var> ends any update unit in progress and begins a non-backoutable update unit. For more information about <var class="product">Model 204</var> update units, see [[File integrity and recovery#Update units and transactions|Update units and transactions]].</li> | ||
< | |||
<li>For more information about the <var>FILELOAD</var> command, the File Load utility, the File Load statements, and input data set requirements, see [[:Category:File loading and reorganization]]. </li> | |||
</ul> | |||
[[Category: File manager commands]] | [[Category: File manager commands]] | ||
[[Category:Commands]] | [[Category:Commands]] |
Latest revision as of 18:18, 9 May 2017
Summary
- Privileges
- File manager (as User 0 only)
- Function
- Starts a File Load (single-step) program
Syntax
FILELOAD k, n, m [,[s1] [,[s2] [,[s3] [,[s4] [,v1]]]]]
Where:
k | The maximum number of records to be loaded into the Model 204 file. |
---|---|
n | The maximum number of times that the statements in the File Load program are to be executed. |
m | The number of input records to skip before starting the load process. |
s1 | The amount of memory that the sort uses for sorting the deferred update index records produced by the File Load program. If s1 is omitted or is not a positive integer, a default value of 50000 bytes (64K for z/VM) is used for the sort work space.
It is important to increase s1 for large sorts. The s1 parameter should be made as large as practical, especially for sorts involving many records. |
s2 | The amount of memory to be used for sorting the deferred update FRV index records. It defaults to 50000 bytes (64K for z/VM) if s2 is omitted or is not a positive integer. For 3380 disk drives, the minimum values for s1 and s2 are 64000 bytes. |
s3 | The amount of memory to be allocated for the two buffers used to pass data from Model 204 to the sorts. This parameter specifies the combined size of the two buffers. The core specified in s3 is evenly divided between the two buffers, and s3 defaults to 8000 bytes.
The minimum value accepted is 48 bytes, but such a small size is not recommended. Larger sizes might produce a noticeable performance improvement. An increase in s1 normally has a greater effect on performance than a corresponding increase in s31. |
s4 | The amount of memory that is allocated for the two buffers used to pass data from the sorts to Model 204. s4 is ordinarily equal in size to s3, and it is set equal to s3 by default. |
vl | The maximum sort record length in variable-length record sorts.
The vl parameter is required when ORDERED fields are updated by the File Load program. For efficiency, the vl option should not be present when ORDERED fields are not updated. For more information on the vl option, see Setting the variable-length sort parameter (vl). |
Syntax notes
- FILELOAD must be issued in file context (that is, the current default must be a file, not a group).
- Specify commas to hold places for missing arguments. When an argument is missing, the default value (if any) is used. (See the examples below.)
Example
OPEN CENSUS FILELOAD -1, -1, 1,102400, 100 G HOUSEHOLD ID=1,5,X'804C' SEX=6,1,X'0410' UNKNOWN=MALE=FEMALE= PLACE SIZE=9,2,X'0410' UNKNOWN= FARM=RURAL=URBAN=5000=10000= 25000=50000=100000=250000= 500000=1000000= OVER 1000000= END
In the following example, arguments s1 and s4 are missing (default values are used):
FILELOAD -1, -1, 1,,1000, 1000
Usage notes
- The FILELOAD command invokes the File Load (FLOD) utility. It is used when a single-step File Load procedure is being performed.
The FLOD command is used to invoke a multistep File Load procedure.
Note: For a site that is authorized for Fast/Reload, the FLOD and FILELOAD commands are syntactically unchanged but invoke Fast/Reload, which compiles and executes the FLOD and FILELOAD programs.
- The FILELOAD command is not supported under z/VSE.
- FILELOAD signals the start of a File Load program, which consists of special statements that load data from a sequential file into a Model 204 file.
To make the File Load program execute efficiently, set the MAXBUF parameter to a value between 5 and 10. Also, make the value of the s1 attribute as large as is practical. The exceptions to these guidelines are:
- FILELOADs of hash-order files that do not use the sort exit M204HASH
- FILELOADs that extensively use the locate statement
- The Model 204 FILELOAD exit feature allows for modification of the record image upon which the FILELOAD (or FILELOADX) command acts. With the FILELOAD exit feature, you can create a COBOL or Assembler program to modify the image records. The FILELOAD exit feature enables the use of more than one input file for FILELOAD processing. The FILELOAD exit is modeled on SORT exits, similar to the E15 sort exit. The FILELOAD exit feature is documented in FLOD exits.
- When it processes FILELOAD, Model 204 ends any update unit in progress and begins a non-backoutable update unit. For more information about Model 204 update units, see Update units and transactions.
- For more information about the FILELOAD command, the File Load utility, the File Load statements, and input data set requirements, see Category:File loading and reorganization.