rm_ch2.htm

db.* (pronounced dee-be star) is an advanced, high performance, small footprint embedded database fo

<p><font size="2">&lt;&lt;<i>STRING</i></font></p>
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<p><font size="2">Search backward for <i>STRING</i>.</font></p>
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<p><b><font size="2">write</font> <i>STRING</i></b></p>
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<p><font size="2">Write <i>STRING</i> into current
position.</font></p>
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<p><b><font size="2">cancel</font></b></p>
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<p><font size="2">Erase all edits since entering hex edit
mode.</font></p>
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<p><b><font size="2">end</font></b></p>
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<p><font size="2">End hex edit mode.</font></p>
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<p><b><font size="2">help</font></b></p>
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<p><font size="2">Print a short list of these commands. You can
also enter a question mark ('?') to invoke this command.</font></p>
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<p><font size="2">&nbsp;</font></p>
<hr>
<h3><a name="dbexp" id="dbexp"></a>dbexp</h3>
<p><font size="2">Database export utility</font></p>
<h4>Prototype</h4>
<pre>
<font color=
"#0000FF">dbexp [-r] [-m] [-n] [-s <i>ch</i>] [-e <i>ch</i>] [-d] [-x] <i>dbname</i> [<i>recname</i>]</font>
</pre>
<h4>Description</h4>
<p><font size="2">This utility exports data from database
<i>dbname</i> to an ASCII text file that can then be moved to
another computer, or used as input into other tools that read ASCII
formatted files (for example, <b>dbimp</b>). The <b>dbexp</b>
utility writes all data from each record type to a separate file;
it is the record name with file extension <b>.txt</b>. If a record
name, <i>recname</i>, is specified on the command line, then only
that record type's occurrences are exported. The created files will
consist of one text line per record occurrence with commas
separating the data fields.</font></p>
<p>The <b>dbexp</b> utility has two ways of printing extended ASCII
characters to the output files when a country table is not being
used. The default is to write out the octal value. Since
<b>dbimp</b> cannot handle this method, the -x option can be used
to print the extended ASCII character as the character. For
example, ASCII 2 would be printed as "\002" without the -x and as a
smiley face with the -x option. (When a country table is used and
the input character has been mapped to something, the "display as"
character will be printed to the text file instead of the "input"
character.)</p>
<h4>Options</h4>
<p><font size="2">-r<br>
Prints a record's database address as the first field of each
record occurrence.</font></p>
<p>-m<br>
Prints the database addresses of the owners of all sets for which
the record is a member.</p>
<p>-n<br>
Silent option. No output to <b>stdout</b>.</p>
<p>-s <i>ch</i><br>
Changes the field separator character from a comma to character
<i>ch</i>. White space between the 's' and the character is
optional.</p>
<p>-e <i>ch</i><br>
Changes the escape from a backslash ('\') to character <i>ch</i>.
White space between the 'e' and the character is optional.</p>
<p>-d<br>
Causes a database address to be printed as long integers, rather
than in the standard format.</p>
<p>-x<br>
Prints the extended ASCII character as the character.</p>
<p>&nbsp;</p>
<hr>
<h3><a name="dbimp" id="dbimp"></a>dbimp</h3>
<p><font size="2">Database import utility</font></p>
<h4>Prototype</h4>
<pre>
<font color=
"#0000FF">dbimp [-n] [-p<i>n</i>] [-s <i>ch</i>] [-e <i>ch</i>] [-k<i>n</i>] <i>impspec</i></font>
</pre>
<h4>Description</h4>
<p><font size="2">This utility imports data into a
<b><i>db.*</i></b> database from ASCII text files according to
commands contained in an import specification file, <b>impspec</b>.
Refer to Chapter 8, "Interactive Database Access Utility
(<b>ida</b>)," of the <b><i>db.*</i></b> <i>User's Guide</i> for
complete information. See the <b>tims</b> example (supplied on the
installation disk) for example usage.</font></p>
<p>The <b>dbimp</b> error message format is:</p>
<div style="margin-left: 4em">
<pre>
<font color="#0000FF">filename line col : message</font>
</pre></div>
<p><font size="2">which is interpreted by some text
editors.</font></p>
<p>Limitations on the ASCII input file are as follows:</p>
<ul>
<li>Maximum line length = 4300 bytes</li>
<li>Maximum field length = 1024 bytes</li>
<li>Maximum fields per line = 128</li>
</ul>
<h4>Options</h4>
<p><font size="2">-n<br>
Prevents <b>dbimp</b> from echoing its input data to standard
output.</font></p>
<p>-p<i>n</i><br>
Changes the number of pages used in the <b><i>db.*</i></b> cache
from 64 to <i>n</i>. Use a smaller value to save memory. Use a
larger value to increase performance.</p>
<p><i>-</i>s <i>ch</i><br>
Changes the field separator character from a comma to character
<i>ch</i>.</p>
<p>-e <i>ch</i><br>
Changes the escape from a backslash ('\') to character
<i>ch</i>.</p>
<p>-k<i>n</i><br>
Changes the record index field length from the default of 25 bytes
to <i>n</i>, where <i>n</i> is any number from 2 to 228. It is
necessary to use longer lengths when input data is not unique up
through 25 characters, and the <b>find on, update on</b>, or
<b>create on</b> options are exercised. Shorter lengths may be
specified to increase performance and decrease the size of a
temporary file.</p>
<h4>Language Summary</h4>
<p><b><font size="2">Import Specification</font></b></p>
<pre>
<font color="#0000FF">database <i>dbname</i> {
   for_loop
   ...
}

for_loop:
   <b>foreach</b> <i>input_file</i> {
      import_statement
      ...
   }

import_statement:
   for_loop | record_statement | connect_statement

record_statement:
   <b>record</b> <i>recname</i> {
      [ handling; ]
      [ field_statement; ]
      ...
   }

handling:
   <b>create on</b> <i>fldnum</i> |
   <b>update on</b> <i>fldnum</i> |
   <b>find on</b> <i>fldnum
</i>
field_statement:
   <b>field</b> <i>fldname</i> = [<i>input_file</i>.]<i>fldnum</i> 

connect_statement:
   <b>connect</b> <i>setname</i></font>
</pre>
<p><font size="2">where the language elements are defined as
follows:</font></p>
<p><i>dbname</i><br>
The full name of the database that is the target of the import. A
path cannot be specified in the statement, but the path that is
specified in the DBDPATH environment variable or in the
<b>db.star.ini</b> file will be utilized.</p>
<p><i>input_file</i><br>
The full name, optionally including a full path, of an ASCII text
file to be used as input. The name of the file must be enclosed in
double-quotes (<b>"</b> <b>"</b>). Note that one input file may be
opened more than once during an import.</p>
<p><i>recname</i><br>
A <b><i>db.*</i></b> record type that is defined in database
<i>dbname</i>.</p>
<p><i>fldnum</i><br>
An integer that identifies a field within <i>input_file</i>. The
first input field is number 1, the second is 2, etc.</p>
<p><i>fldname</i><br>
A <b><i>db.*</i></b> field type that is defined in database
<i>dbname</i>, within the record type created by the
record_statement enclosing this statement.</p>
<p><i>setname</i><br>
A <b><i>db.*</i></b> set type that is defined in database
<i>dbname</i>.</p>
<p>&nbsp;</p>
<hr>
<h3><a name="dchain" id="dchain"></a>dchain</h3>
<p><font size="2">Delete chain sort utility</font></p>
<h4>Prototype</h4>
<pre>
<font color=
"#0000FF">dchain <i>dbname </i>[<i>dbfile</i>]...</font>
</pre>
<h4>Description</h4>
<p><font size="2">The <b>dchain</b> utility sorts the deleted
record slots on the delete chains of the listed data files
([<i>dbfile</i>]...) from database <i>dbname</i> in database
address order. If no files are listed, all data files in database
<i>dbname</i> will be processed. This utility does not sort key
file delete chains.</font></p>
<p>The purpose of this utility is to increase the probability that
newly created records in the same file will be placed close
together. The extent of any performance improvement, however, will
depend upon the application. The most likely time to use this
utility is after a periodic purge of a particular set of record
types, many of which were entered together; thus there would be
many contiguous record slots on the delete chain.</p>
<h4>Options</h4>
<p><font size="2">None.</font></p>
<p>&nbsp;</p>
<hr>
<h3><a name="ddlp" id="ddlp"></a>ddlp</h3>
<p><font size="2">Database definition language processor</font></p>
<h4>Prototype</h4>
<pre>
<font color=
"#0000FF">ddlp [-r] [-x] [-d] [-n] [-s[-]] [-z] [-c] <i>ddlfile</i></font>
</pre>
<h4>Description</h4>
<p><font size="2">The database definition language processor,
<b>ddlp</b>, compiles the DDL specification contained in the text
file <i>ddlfile</i>, and generates the database dictionary
(&lt;<b>dbname</b>&gt;<b>.dbd</b> ), the database header file
(&lt;<b>dbname</b>&gt;<b>.h</b>), and, optionally source code
database schema dictionary (&lt;<b>dbname</b>&gt;<b>.c</b>). DDL
errors will be reported on <b>stdout</b> with the line number where
the error was first detected. See the <b>tims</b> example (supplied
with the product) for more information.</font></p>
<p>Be sure to refer to the list of <b>ddlp</b> keywords listed at
the end of this section.</p>
<blockquote><b><i>Note:</i></b> Sometimes the reported error line
number is the line following the place where the actual error
occurs. Be sure to check the lines preceding the reported line if
you cannot find the error in the reported line.</blockquote>
<p><font size="2">The <b>ddlp</b> error message format
is</font></p>
<div style="margin-left: 4em">
<pre>
<font color="#0000FF">filename line col : message</font>
</pre></div>
<p><font size="2">which some text editors interpret.</font></p>
<h4>Options</h4>
<p><font size="2">-r<br>
Generates the file structure report.</font></p>
<p>-x<br>
Generates a cross-reference listing of record, set, and field
names.</p>
<p>-d<br>
Allows two records to have the same field name, for example:</p>
<pre>
<font color="#0000FF">record a {
   char idcode[w];
}
record b {
   key int idcode;
}</font>
</pre>
<p><font size="2">-n<br>
Instructs <b>ddlp</b> to omit writing the ASCII record, set, and
field names to the dictionary file. This option creates a smaller
dictionary file, but it makes names unavailable to utilities such
as <b>ida</b> and <b>dbimp</b>.</font></p>
<p>-s[-]<br>
Instructs <b>ddlp</b> to preserve the case of record, set, and
field names. If -s- is specified, everything is converted to
uppercase. Case sensitivity is the default, so this option has been
added for backward compatibility.</p>
<p>-z<br>
Instructs <b>ddlp</b> to omit the creation of the SIZEOF_*
definitions.</p>
<p>-c<br>
Instructs <b>ddlp</b> to produce source code schema definition file
<b>&lt;dbname&gt;.c</b>.</p>
<h4>Language Summary</h4>
<pre>
<font color=
"#0000FF">database <i>dbname</i> [<i> </i>[<i>pgsize</i>]<i> </i>] {
   [ timestamp ]
   ...
   file_stmt
   ...
   record_stmt
   ...
   [ set_stmt ]
   ...
}

timestamp:
   <b>timestamp</b> <b>records</b> <i>recname </i>[, <i>recname</i>]...;
or
   <b>timestamp</b> <b>sets</b> <i>setname </i>[, <i>setname</i>]...;

file_stmt:
   <b>data file</b> [<b>[</b><i>pgsize</i><b>]</b>]<i> </i>[<i>fileid</i> =]<i> filename</i> <b>contains
</b>      <i>recname </i>[, <i>recname</i>]...;
or
   <b>key file</b> [<b>[</b><i>pgsize</i><b>]</b>]<i> </i>[<i>fileid</i> =]<i> filename</i> <b>contains
</b>      <i>keyname</i> [, <i>keyname</i>]...;

record_stmt:
   <b>record</b> <i>recname</i> {
      [field_stmt]
      ...
      [comkey_stmt]
      ...
   }

field_stmt:
   [[<b>optional</b>] [<b>unique</b>] <b>key</b>] type <i>fldname </i>[ <b>[</b><i>dim</i><b>]</b>...];
or
   [[<b>optional</b>] [<b>unique</b>] <b>key</b>] <b>struct</b> {
      field_stmt
      ...
   } <i>fldname </i>[ <b>[</b>dim<b>]</b>...] ;

type:
   [<b>unsigned</b>] { <b>int</b> |<i> </i><b>short</b> | <b>long</b> } |
   <b>char</b> | <b>float</b> | <b>double</b> | <b>db_addr
</b>
comkey_stmt:
   <b>compound</b> [<b>optional</b>] [<b>unique</b>] <b>key field</b> <i>keyname</i> {
      <i>fldname</i> [ <b>ascending</b> | <b>descending</b> ] ;
      ...
   }

set_stmt:
   [ <b>blob</b> | <b>bitmap</b> | <b>varilen</b> ] <b>set</b> <i>setname</i> {
      <b>order</b> ordering ;
      <b>owner</b> <i>recname</i> ;
      <b>member</b> <i>recname</i> [<b>by</b> <i>fldname</i> [, <i>fldname</i>]...] ;
      ...
   }

ordering:
   <b>ascending</b> | <b>descending</b> | <b>first</b> | <b>last</b> | <b>next</b></font>
</pre>
<p><font size="2">where the language elements are defined as
follows:</font></p>
<p><i>dbname</i><br>
An identifier that names the database.</p>
<p><i>pgsize</i><br>
The default size of a database page. (If <i>pgsize</i> is not
supplied, the default is 1,024 bytes or the smallest multiple of
512 that will still hold the largest record.)</p>