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diff --git a/bdb/tcl/docs/db.html b/bdb/tcl/docs/db.html new file mode 100644 index 00000000000..c75ab6ecf4f --- /dev/null +++ b/bdb/tcl/docs/db.html @@ -0,0 +1,266 @@ +<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> +<HTML> +<HEAD> + <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=iso-8859-1"> + <META NAME="GENERATOR" CONTENT="Mozilla/4.08 [en] (X11; I; FreeBSD 3.3-RELEASE i386) [Netscape]"> +</HEAD> +<BODY> + +<H2> +<A NAME="Database Commands"></A>Database Commands</H2> +The database commands provide a conduit into the DB method functions. +They are all fairly straightforward and I describe them in terms of their +DB functions briefly here, with a link to the DB page where appropriate. +The first set of commands are those I believe will be the primary functions +used by most databases. Some are directly related to their DB counterparts, +and some are higher level functions that are useful to provide the user. +<P><B>> berkdb open [-env <I>env</I>]</B> +<BR><B> [-btree|-hash|-recno|-queue|-unknown]</B> +<BR><B> [-create] [-excl] [-nommap] [-rdonly] [-truncate] +[-mode +<I>mode</I>] [-errfile <I>filename</I>]</B> +<BR><B> [-dup] [-dupsort] [-recnum] [-renumber] [-revsplitoff] +[-snapshot]</B> +<BR><B> [-extent <I>size</I>]</B> +<BR><B> [-ffactor <I>density</I>]</B> +<BR><B> [-nelem <I>size</I>]</B> +<BR><B> [-lorder <I>order</I>]</B> +<BR><B> [-delim <I>delim</I>]</B> +<BR><B> [-len <I>len</I>]</B> +<BR><B> [-pad <I>pad</I>]</B> +<BR><B> [-source <I>file</I>]</B> +<BR><B> [-minkey <I>minkey</I>]</B> +<BR><B> [-cachesize {<I>gbytes bytes ncaches</I>}]</B> +<BR><B> [-pagesize <I>pagesize</I>]</B> +<BR><B> [--]</B> +<BR><B> [<I>filename </I>[<I>subdbname</I>]]</B> +<P>This command will invoke the <A HREF="../../docs/api_c/db_create.html">db_create</A> +function. If the command is given the <B>-env</B> option, then we +will accordingly creating the database within the context of that environment. +After it successfully gets a handle to a database, we bind it to a new +Tcl command of the form <B><I>dbX, </I></B>where X is an integer starting +at 0 (e.g. <B>db0, db1, </B>etc). We use the <I>Tcl_CreateObjCommand() </I> +to create the top level database function. It is through this handle +that the user can access all of the commands described in the <A HREF="#Database Commands">Database +Commands</A> section. Internally, the database handle is sent as +the <I>ClientData</I> portion of the new command set so that all future +database calls access the appropriate handle. +<P>After parsing all of the optional arguments affecting the setup of the +database and making the appropriate calls to DB to manipulate those values, +we open the database for the user. It translates to the +<A HREF="../../docs/api_c/db_open.html">DB->open</A> +method call after parsing all of the various optional arguments. +We automatically set the DB_THREAD flag. The arguments are: +<UL> +<LI> +<B>-- </B>- Terminate the list of options and use remaining arguments as +the file or subdb names (thus allowing the use of filenames beginning with +a dash '-')</LI> + +<LI> +<B>-btree</B> - DB_BTREE database</LI> + +<LI> +<B>-hash</B> - DB_HASH database</LI> + +<LI> +<B>-recno </B> - DB_RECNO database</LI> + +<LI> +<B>-queue</B> - DB_QUEUE database</LI> + +<LI> +<B>-create</B> selects the DB_CREATE flag to create underlying files</LI> + +<LI> +<B>-excl</B> selects the DB_EXCL flag to exclusively create underlying +files</LI> + +<LI> +<B>-nommap</B> selects the DB_NOMMAP flag to forbid mmaping of files</LI> + +<LI> +<B>-rdonly</B> selects the DB_RDONLY flag for opening in read-only mode</LI> + +<LI> +<B>-truncate</B> selects the DB_TRUNCATE flag to truncate the database</LI> + +<LI> +<B>-mode<I> mode</I></B> specifies the mode for created files</LI> + +<LI> +<B>-errfile </B>specifies the error file to use for this environment to +<B><I>filename</I></B> +by calling <A HREF="../../docs/api_c/db_set_errfile.html">DB->set_errfile</A><B><I>. +</I></B>If +the file already exists then we will append to the end of the file</LI> + +<LI> +<B>-dup </B>selects the DB_DUP flag to permit duplicates in the database</LI> + +<LI> +<B>-dupsort</B> selects the DB_DUPSORT flag to support sorted duplicates</LI> + +<LI> +<B>-recnum</B> selects the DB_RECNUM flag to support record numbers in +btrees</LI> + +<LI> +<B>-renumber </B>selects the DB_RENUMBER flag to support mutable record +numbers</LI> + +<LI> +<B>-revsplitoff </B>selects the DB_REVSPLITOFF flag to suppress reverse +splitting of pages on deletion</LI> + +<LI> +<B>-snapshot </B>selects the DB_SNAPSHOT flag to support database snapshots</LI> + +<LI> +<B>-extent </B>sets the size of a Queue database extent to the given <B><I>size +</I></B>using +the <A HREF="../../docs/api_c/db_set_q_extentsize.html">DB->set_q_extentsize</A> +method</LI> + +<LI> +<B>-ffactor</B> sets the hash table key density to the given <B><I>density +</I></B>using +the <A HREF="../../docs/api_c/db_set_h_ffactor.html">DB->set_h_ffactor</A> +method</LI> + +<LI> +<B>-nelem </B>sets the hash table size estimate to the given <B><I>size +</I></B>using +the <A HREF="../../docs/api_c/db_set_h_nelem.html">DB->set_h_nelem</A> +method</LI> + +<LI> +<B>-lorder </B>sets the byte order for integers stored in the database +meta-data to the given <B><I>order</I></B> using the <A HREF="../../docs/api_c/db_set_lorder.html">DB->set_lorder</A> +method</LI> + +<LI> +<B>-delim </B>sets the delimiting byte for variable length records to +<B><I>delim</I></B> +using the <A HREF="../../docs/api_c/db_set_re_delim.html">DB->set_re_delim</A> +method</LI> + +<LI> +<B>-len </B>sets the length of fixed-length records to <B><I>len</I></B> +using the <A HREF="../../docs/api_c/db_set_re_len.html">DB->set_re_len</A> +method</LI> + +<LI> +<B>-pad </B>sets the pad character used for fixed length records to +<B><I>pad</I></B> +using the <A HREF="../../docs/db_set_re_pad.html">DB->set_re_pad</A> method</LI> + +<LI> +<B>-source </B>sets the backing source file name to <B><I>file</I></B> +using the <A HREF="../../docs/api_c/db_set_re_source.html">DB->set_re_source</A> +method</LI> + +<LI> +<B>-minkey </B>sets the minimum number of keys per Btree page to <B><I>minkey</I></B> +using the <A HREF="../../docs/api_c/db_set_bt_minkey.html">DB->set_bt_minkey</A> +method</LI> + +<LI> +<B>-cachesize </B>sets the size of the database cache to the size +specified by <B><I>gbytes </I></B>and <B><I>bytes, </I></B>broken up into +<B><I>ncaches</I></B> +number of caches using the <A HREF="../../docs/api_c/db_set_cachesize.html">DB->set_cachesize</A> +method</LI> + +<LI> +<B>-pagesize </B>sets the size of the database page to <B><I>pagesize </I></B>using +the <A HREF="../../docs/api_c/db_set_pagesize.html">DB->set_pagesize</A> +method</LI> + +<LI> +<B><I>filename</I></B> indicates the name of the database</LI> + +<LI> +<B><I>subdbname</I></B> indicate the name of the sub-database</LI> +</UL> + +<HR WIDTH="100%"> +<BR><B> berkdb upgrade [-dupsort] [-env <I>env</I>] [--] [<I>filename</I>]</B> +<P>This command will invoke the <A HREF="../../docs/api_c/db_upgrade.html">DB->upgrade</A> +function. If the command is given the <B>-env</B> option, then we +will accordingly upgrade the database filename within the context of that +environment. The <B>-dupsort</B> option selects the DB_DUPSORT flag for +upgrading. The use of --<B> </B>terminates the list of options, thus allowing +filenames beginning with a dash. +<P> +<HR WIDTH="100%"><B>> berkdb verify [-env <I>env</I>] [--] [<I>filename</I>]</B> +<P>This command will invoke the <A HREF="../../docs/api_c/db_verify.html">DB->verify</A> +function. If the command is given the <B>-env</B> option, then we +will accordingly verify the database filename within the context of that +environment. The use of --<B> </B>terminates the list of options, +thus allowing filenames beginning with a dash. +<P> +<HR WIDTH="100%"><B>> <I>db</I> join [-nosort] <I>db0.c0 db1.c0</I> ...</B> +<P>This command will invoke the <A HREF="../../docs/api_c/db_join.html">db_join</A> +function. After it successfully joins a database, we bind it to a +new Tcl command of the form <B><I>dbN.cX, </I></B>where X is an integer +starting at 0 (e.g. <B>db2.c0, db3.c0, </B>etc). We use the <I>Tcl_CreateObjCommand() </I> +to create the top level database function. It is through this cursor +handle that the user can access the joined data items. +<P>The options are: +<UL> +<LI> +<B>-nosort -</B> This flag causes DB not to sort the cursors based on the +number of data items they reference. It results in the DB_JOIN_NOSORT +flag being set.</LI> +</UL> + +<HR WIDTH="100%"><B>> <I>db</I> get_join [-nosort] {db key} {db key} ...</B> +<P>This command performs a join operation on the keys specified and returns +a list of the joined {key data} pairs. +<P>The options are: +<UL> +<LI> +<B>-nosort</B> This flag causes DB not to sort the cursors based on the +number of data items they reference. It results in the DB_JOIN_NOSORT +flag being set.</LI> +</UL> + +<HR WIDTH="100%"><B>> <I>db</I> keyrange [-txn <I>id</I>] key</B> +<P>This command returns the range for the given <B>key</B>. It returns +a list of 3 double elements of the form {<B><I>less equal greater</I></B>} +where <B><I>less</I></B> is the percentage of keys less than the given +key, <B><I>equal</I></B> is the percentage equal to the given key and <B><I>greater</I></B> +is the percentage greater than the given key. If the -txn option +is specified it performs this operation under transaction protection. +<BR> +<HR WIDTH="100%"><B>> <I>db</I> put</B> +<P>The <B>undocumented</B> options are: +<UL> +<LI> +<B>-nodupdata</B> This flag causes DB not to insert the key/data pair if +it already exists, that is, both the key and data items are already in +the database. The -nodupdata flag may only be specified if the underlying +database has been configured to support sorted duplicates.</LI> +</UL> + +<HR WIDTH="100%"><B>> <I>db</I> stat</B> +<P>The <B>undocumented</B> options are: +<UL> +<LI> +<B>-cachedcounts</B> This flag causes DB to return the cached key/record +counts, similar to the DB_CACHED_COUNTS flags to DB->stat.</LI> +</UL> + +<HR WIDTH="100%"><B>> <I>dbc</I> put</B> +<P>The <B>undocumented</B> options are: +<UL> +<LI> +<B>-nodupdata</B> This flag causes DB not to insert the key/data pair if +it already exists, that is, both the key and data items are already in +the database. The -nodupdata flag may only be specified if the underlying +database has been configured to support sorted duplicates.</LI> +</UL> + +</BODY> +</HTML> |