<!--$Id: seq_stat.so,v 1.9 2007/06/22 16:57:17 bostic Exp $--> <!--Copyright (c) 1997,2008 Oracle. All rights reserved.--> <!--See the file LICENSE for redistribution information.--> <html> <head> <title>Berkeley DB: DB_SEQUENCE->stat</title> <meta name="description" content="Berkeley DB: An embedded database programmatic toolkit."> <meta name="keywords" content="embedded,database,programmatic,toolkit,btree,hash,hashing,transaction,transactions,locking,logging,access method,access methods,Java,C,C++"> </head> <body bgcolor=white> <table width="100%"><tr valign=top> <td> <b>DB_SEQUENCE->stat</b> </td> <td align=right> <a href="../api_c/api_core.html"><img src="../images/api.gif" alt="API"></a> <a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a></td> </tr></table> <hr size=1 noshade> <tt> <b><pre> #include <db.h> <p> int DB_SEQUENCE->stat(DB_SEQUENCE *db, void *sp, u_int32_t flags); <p> int DB_SEQUENCE->stat_print(DB_SEQUENCE *db, u_int32_t flags); </pre></b> <hr size=1 noshade> <b>Description: DB_SEQUENCE->stat</b> <p>The DB_SEQUENCE->stat method creates a statistical structure and copies a pointer to it into user-specified memory locations. Specifically, if <b>sp</b> is non-NULL, a pointer to the statistics for the database are copied into the memory location to which it refers.</p> <p>Statistical structures are stored in allocated memory. If application-specific allocation routines have been declared (see <a href="../api_c/env_set_alloc.html">DB_ENV->set_alloc</a> for more information), they are used to allocate the memory; otherwise, the standard C library <b>malloc</b>(3) is used. The caller is responsible for deallocating the memory. To deallocate the memory, free the memory reference; references inside the returned memory need not be individually freed.</p> <p>In the presence of multiple threads or processes accessing an active sequence, the information returned by DB_SEQUENCE->stat may be out-of-date.</p> <p>The DB_SEQUENCE->stat method cannot be transaction-protected. For this reason, it should be called in a thread of control that has no open cursors or active transactions.</p> <p>The statistics are stored in a structure of type DB_SEQUENCE_STAT. The following fields will be filled in:</p> <br> <b>u_int32_t st_wait;</b><ul compact><li>The number of times a thread of control was forced to wait on the handle mutex.</ul> <b>u_int32_t st_nowait;</b><ul compact><li>The number of times that a thread of control was able to obtain handle mutex without waiting.</ul> <b>db_seq_t st_current;</b><ul compact><li>The current value of the sequence in the database.</ul> <b>db_seq_t st_value;</b><ul compact><li>The current cached value of the sequence.</ul> <b>db_seq_t st_last_value;</b><ul compact><li>The last cached value of the sequence.</ul> <b>db_seq_t st_min;</b><ul compact><li>The minimum permitted value of the sequence.</ul> <b>db_seq_t st_max;</b><ul compact><li>The maximum permitted value of the sequence.</ul> <b>int32_t st_cache_size;</b><ul compact><li>The number of values that will be cached in this handle.</ul> <b>u_int32_t st_flags;</b><ul compact><li>The flags value for the sequence.</ul> <br> <b>Parameters</b> <br> <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set by bitwise inclusively <b>OR</b>'ing together one or more of the following values: <br> <b><a name="DB_STAT_CLEAR">DB_STAT_CLEAR</a></b><ul compact><li>Reset statistics after printing their values.</ul> <br></ul> <br> <p>The DB_SEQUENCE->stat method may not be called before the <a href="../api_c/seq_open.html">DB_SEQUENCE->open</a> method has been called.</p> <p>The DB_SEQUENCE->stat method returns a non-zero error value on failure and 0 on success. </p> <hr size=1 noshade> <b>Description: DB_SEQUENCE->stat_print</b> <p>The DB_SEQUENCE->stat_print method prints diagnostic information to the output channel described by the <a href="../api_c/env_set_msgfile.html">DB_ENV->set_msgfile</a> method.</p> <b>Parameters</b> <br> <b>flags</b><ul compact><li>The <b>flags</b> parameter must be set by bitwise inclusively <b>OR</b>'ing together one or more of the following values: <br> <b><a name="DB_STAT_CLEAR">DB_STAT_CLEAR</a></b><ul compact><li>Reset statistics after printing their values.</ul> <br></ul> <br> <hr size=1 noshade> <br><b>Class</b> <a href="../api_c/seq_class.html">DB_SEQUENCE</a> <br><b>See Also</b> <a href="../api_c/seq_list.html">Sequences and Related Methods</a> </tt> <table width="100%"><tr><td><br></td><td align=right> <a href="../api_c/api_core.html"><img src="../images/api.gif" alt="API"></a><a href="../ref/toc.html"><img src="../images/ref.gif" alt="Ref"></a> </td></tr></table> <p><font size=1>Copyright (c) 1996,2008 Oracle. All rights reserved.</font> </body> </html>