use of pg_stat_database

<table border="0" cellpadding="0" cellspacing="0"><tr><td style="font: inherit;" valign="top"><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">Hellow,</font></font></span><pclass="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span lang="EN-GB"
style="mso-ansi-language:EN-GB"><font size="3"><font face="Times New Roman"></font></font></span>  <p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">Ilike to track the number of committed transaction for my database</font></font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">SoI use the following command </font></font></span><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span
lang="EN-GB"style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New Roman">Select * from
pg_stat_database;</font></font></span><pclass="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span lang="EN-GB"
style="mso-ansi-language:EN-GB"><font face="Times New Roman" size="3"> </font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">Thecolumn xact_commit gives me the number of transaction committed</font></font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font face="Times New Roman"
size="3"> </font></span><pclass="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language:
EN-GB"><fontsize="3"><font face="Times New Roman">But if I execute the same command another time, the column
xact_commitgives me an other number.</font></font></span><p class="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span
lang="EN-GB"style="mso-ansi-language: EN-GB"><font face="Times New Roman" size="3"> </font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">Betweenthe first select and the second select I don’t execute any transaction on my
database</font></font></span><pclass="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span lang="EN-GB"
style="mso-ansi-language:EN-GB"><font face="Times New Roman" size="3"> </font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font size="3"><font face="Times New
Roman">Please,can any one help me to understanding the cause of the change?</font></font></span><p class="MsoNormal"
style="MARGIN:0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language: EN-GB"><font face="Times New Roman"
size="3"> </font></span><pclass="MsoNormal" style="MARGIN: 0cm 0cm 0pt"><span lang="EN-GB" style="mso-ansi-language:
EN-GB"><fontsize="3"><font face="Times New Roman">Thanks very much </font></font></span></td></tr></table><br />