oracle10g系统管理之序列

<p class="MsoNormal" style=""><span style="" lang="EN-US"><span style=""><span style="font-family: Times New Roman;"><span style="font-size: small;">1.</span><span style='font: 7pt "Times New Roman";'> </span></span></span></span><span style=""><span style="font-size: small;">建立序列</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">CREATE SEQUENCE deptno_seq</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">START WITH 50 INCREMENT BY 10</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">MAXVALUE 99 CACHE 10;</span></span></p>
<p class="MsoNormal" style=""><span style="" lang="EN-US"><span style=""><span style="font-family: Times New Roman;"><span style="font-size: small;">2.</span><span style='font: 7pt "Times New Roman";'> </span></span></span></span><span style=""><span style="font-size: small;">使用序列</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">INSERT INTO dept(deptno,dname,loc)</span></span></p>
<p class="MsoNormal" style=""><span style="" lang="EN-US"><span style=""><span style="font-family: Times New Roman;"><span style="font-size: small;">3.</span><span style='font: 7pt "Times New Roman";'> </span></span></span></span><span style=""><span style="font-size: small;">修改序列</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">ALTER SEQUENCE deptno_seq</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span lang="EN-US"><span style="font-size: small; font-family: Times New Roman;">MAXVALUE 200 CACHE 20;</span></span></p>
<p class="MsoNormal" style="margin: 0cm 0cm 0pt 21pt;"><span style="font-size: small;"><span lang="EN-US"><span style="font-family: Times New Roman;">VALUES</span></span><span style="">（</span><span lang="EN-US"><span style="font-family: Times New Roman;">deptno_seq.NEXTVAL,’DEVELOPMENT’,DEFAULT</span></span><span style="">）</span><span lang="EN-US"><span style="font-family: Times New Roman;">;</span></span></span></p>
<p class="MsoNormal" style=""><span style="" lang="EN-US"><span style=""><span style="font-family: Times New Roman;"><span style="font-size: small;">4.</span><span style='font: 7pt "Times New Roman";'> </span></span></span></span><span style="font-size: small;"><span style="">通过使用</span><span lang="EN-US"><span style="font-family: Times New Roman;">CACHE</span></span><span style="">选项建立序列，可以设置内存中预分配的序列号个数。</span></span></p>
<p class="MsoNormal" style=""><span style="" lang="EN-US"><span style=""><span style="font-family: Times New Roman;"><span style="font-size: small;">5.</span><span style='font: 7pt "Times New Roman";'> </span></span></span></span><span style="font-size: small;"><span style="">执行</span><span lang="EN-US"><span style="font-family: Times New Roman;">ROLLBACK</span></span><span style="">语句取消实务操作时，将导致出现序列缺口。</span></span></p>