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diff --git a/lib/snmp/doc/src/snmpa_local_db.xml b/lib/snmp/doc/src/snmpa_local_db.xml new file mode 100644 index 0000000000..c077bc96d8 --- /dev/null +++ b/lib/snmp/doc/src/snmpa_local_db.xml @@ -0,0 +1,190 @@ +<?xml version="1.0" encoding="latin1" ?> +<!DOCTYPE erlref SYSTEM "erlref.dtd"> + +<erlref> + <header> + <copyright> + <year>1996</year><year>2009</year> + <holder>Ericsson AB. All Rights Reserved.</holder> + </copyright> + <legalnotice> + The contents of this file are subject to the Erlang Public License, + Version 1.1, (the "License"); you may not use this file except in + compliance with the License. You should have received a copy of the + Erlang Public License along with this software. If not, it can be + retrieved online at http://www.erlang.org/. + + Software distributed under the License is distributed on an "AS IS" + basis, WITHOUT WARRANTY OF ANY KIND, either express or implied. See + the License for the specific language governing rights and limitations + under the License. + + </legalnotice> + + <title>snmpa_local_db</title> + <prepared></prepared> + <responsible></responsible> + <docno></docno> + <approved></approved> + <checked></checked> + <date></date> + <rev></rev> + <file>snmpa_local_db.xml</file> + </header> + <module>snmpa_local_db</module> + <modulesummary>The SNMP built-in database</modulesummary> + <description> + <p>The module <c>snmpa_local_db</c> contains functions for + implementing tables (and variables) using the SNMP built-in + database. The database exists in two instances, one volatile + and one persistent. The volatile database is implemented with + ets. The persistent database is implemented with dets. + </p> + <p>There is a scaling problem with this database. + </p> + <list type="bulleted"> + <item>Insertions and deletions are inefficient for large tables. + </item> + </list> + <p>This problem is best solved by using Mnesia instead. + </p> + <p>The following functions describe the interface to + <c>snmpa_local_db</c>. Each function has a Mnesia equivalent. + The argument <c>NameDb</c> is a tuple <c>{Name, Db}</c> where + <c>Name</c> is the symbolic name of the managed object (as defined + in the MIB), and <c>Db</c> is either <c>volatile</c> or + <c>persistent</c>. <c>mnesia</c> is not possible since all these + functions are <c>snmpa_local_db</c> specific. + </p> + </description> + + <section> + <title>Common Data Types</title> + <p>In the functions defined below, the following types are + used: + </p> + <list type="bulleted"> + <item> + <p><c>NameDb = {Name, Db}</c></p> + </item> + <item> + <p><c>Name = atom(), Db = volatile | persistent</c></p> + </item> + <item> + <p><c>RowIndex = [int()]</c></p> + </item> + <item> + <p><c>Cols = [Col] | [{Col, Value}], Col = int(), Value = term()</c></p> + </item> + </list> + <p>where <c>RowIndex</c> denotes the last part of the OID, that + specifies the index of the row in the table. <c>Cols</c> is a + list of column numbers in case of a get operation, and a list of + column numbers and values in case of a set operation. + </p> + </section> + <funcs> + <func> + <name>dump() -> ok | {error, Reason}</name> + <fsummary>Dump the database to disk</fsummary> + <type> + <v>Reason = term()</v> + </type> + <desc> + <p>This function can be used to manually dump the database + to file.</p> + </desc> + </func> + <func> + <name>match(NameDb, Pattern)</name> + <fsummary>Perform a match on the table</fsummary> + <desc> + <p>Performs an ets/dets matching on the table. + See Stdlib documentation, module ets, for a description of + <c>Pattern</c> and the return values.</p> + </desc> + </func> + <func> + <name>print()</name> + <name>print(TableName)</name> + <name>print(TableName, Db)</name> + <fsummary>Print the database to screen</fsummary> + <type> + <v>TableName = atom()</v> + </type> + <desc> + <p>Prints the contents of the database on + screen. This is useful for debugging since the + <c>STANDARD-MIB</c> and <c>OTP-SNMPEA-MIB</c> + (and maybe your own MIBs) are stored in <c>snmpa_local_db</c>. + </p> + <p><c>TableName</c> is an atom for a table in the database. + When no name is supplied, the whole database is shown.</p> + </desc> + </func> + <func> + <name>table_create(NameDb) -> bool()</name> + <fsummary>Create a table</fsummary> + <desc> + <p>Creates a table. If the table already exist, the old copy + is destroyed. + </p> + <p>Returns <c>false</c> if the <c>NameDb</c> argument is + incorrectly specified, <c>true</c> otherwise.</p> + </desc> + </func> + <func> + <name>table_create_row(NameDb, RowIndex, Row) -> bool()</name> + <fsummary>Create a row in a table</fsummary> + <type> + <v>Row = {Val1, Val2, ..., ValN}</v> + <v>Val1 = Val2 = ... = ValN = term()</v> + </type> + <desc> + <p>Creates a row in a table. <c>Row</c> is a tuple with + values for all columns, including the index columns.</p> + </desc> + </func> + <func> + <name>table_delete(NameDb) -> void()</name> + <fsummary>Delete a table</fsummary> + <desc> + <p>Deletes a table.</p> + </desc> + </func> + <func> + <name>table_delete_row(NameDb, RowIndex) -> bool()</name> + <fsummary>Delete the row in the table</fsummary> + <desc> + <p>Deletes the row in the table.</p> + </desc> + </func> + <func> + <name>table_exists(NameDb) -> bool()</name> + <fsummary>Check if a table exists</fsummary> + <desc> + <p>Checks if a table exists.</p> + </desc> + </func> + <func> + <name>table_get_row(NameDb, RowIndex) -> Row | undefined</name> + <fsummary>Get a row from the table</fsummary> + <type> + <v>Row = {Val1, Val2, ..., ValN}</v> + <v>Val1 = Val2 = ... = ValN = term()</v> + </type> + <desc> + <p><c>Row</c> is a tuple with values for all columns, + including the index columns.</p> + </desc> + </func> + </funcs> + + <section> + <title>See Also</title> + <p>ets(3), dets(3), snmp_generic(3) + </p> + </section> + +</erlref> + |