{"id":245,"date":"2025-06-07T20:37:05","date_gmt":"2025-06-07T12:37:05","guid":{"rendered":"https:\/\/zd1269878.noblogs.org\/?p=245"},"modified":"2025-10-21T10:31:25","modified_gmt":"2025-10-21T02:31:25","slug":"%e6%95%b0%e6%8d%ae%e5%ba%93%e7%b3%bb%e7%bb%9f%e7%9f%a5%e8%af%86%e7%82%b9%e6%95%b4%e7%90%86%e4%b8%8e%e7%bb%83%e4%b9%a0","status":"publish","type":"post","link":"https:\/\/zd1269878.noblogs.org\/en-US\/post\/2025\/06\/07\/%e6%95%b0%e6%8d%ae%e5%ba%93%e7%b3%bb%e7%bb%9f%e7%9f%a5%e8%af%86%e7%82%b9%e6%95%b4%e7%90%86%e4%b8%8e%e7%bb%83%e4%b9%a0\/","title":{"rendered":"\u6570\u636e\u5e93\u7cfb\u7edf\u77e5\u8bc6\u70b9\u6574\u7406\u4e0e\u7ec3\u4e60"},"content":{"rendered":"\n



\u4e00\u3001\u77e5\u8bc6\u67b6\u6784<\/a>
1. \u6570\u636e\u5e93\u57fa\u7840\u6982\u5ff5
\u00a0\u00a0 \u251c\u2500 \u6570\u636e\/\u6570\u636e\u5e93\/DBMS\/DBS\u5b9a\u4e49\u4e0e\u533a\u522b
\u00a0\u00a0 \u251c\u2500 \u6570\u636e\u72ec\u7acb\u6027\uff08\u7269\u7406\/\u903b\u8f91\uff09
\u00a0\u00a0 \u251c\u2500 \u6570\u636e\u5e93\u53d1\u5c55\u9636\u6bb5\uff08\u624b\u5de5\u7ba1\u7406\u2192\u6587\u4ef6\u7cfb\u7edf\u2192\u6570\u636e\u5e93\uff09
2. \u6570\u636e\u5e93\u4f53\u7cfb\u7ed3\u6784
\u00a0\u00a0 \u251c\u2500 \u4e09\u7ea7\u6a21\u5f0f\uff08\u5916\u6a21\u5f0f\/\u6a21\u5f0f\/\u5185\u6a21\u5f0f\uff09
\u00a0\u00a0 \u251c\u2500 \u4e24\u7ea7\u6620\u50cf\uff08\u5916\u6a21\u5f0f\/\u6a21\u5f0f\u3001\u6a21\u5f0f\/\u5185\u6a21\u5f0f\uff09
3. \u6570\u636e\u5e93\u8bbe\u8ba1\u4e0e\u5efa\u6a21
\u00a0\u00a0 \u251c\u2500 \u6982\u5ff5\u6a21\u578b\uff08ER\u56fe\u5143\u7d20\u4e0e\u7ed8\u5236\uff09
\u00a0\u00a0 \u251c\u2500 \u6570\u636e\u6a21\u578b\u5206\u7c7b\uff08\u5173\u7cfb\u6a21\u578b\u4e09\u8981\u7d20\uff09
\u00a0\u00a0 \u251c\u2500 \u51fd\u6570\u4f9d\u8d56\u4e0e\u8303\u5f0f\u7406\u8bba\uff081NF\/2NF\/3NF\/BCNF\uff09
4. SQL\u67e5\u8be2\u4e0e\u64cd\u4f5c
\u00a0\u00a0 \u251c\u2500 DDL\/DML\/DCL\/TCL\u57fa\u7840\u8bed\u6cd5
\u00a0\u00a0 \u251c\u2500 \u590d\u6742\u67e5\u8be2\uff08\u591a\u8868\u8fde\u63a5\u3001\u5b50\u67e5\u8be2\u3001\u805a\u5408\u51fd\u6570\uff09
\u00a0\u00a0 \u251c\u2500 \u5173\u7cfb\u4ee3\u6570\u8fd0\u7b97\uff08\u9009\u62e9\/\u6295\u5f71\/\u8fde\u63a5\/\u9664\u6cd5\uff09
5. \u4e8b\u52a1\u4e0e\u5e76\u53d1\u63a7\u5236
\u00a0\u00a0 \u251c\u2500 ACID\u7279\u6027\u4e0e\u9501\u673a\u5236
\u00a0\u00a0 \u251c\u2500 \u65e5\u5fd7\u4e0e\u6062\u590d\u7b56\u7565\uff08UNDO\/REDO\uff09
6. \u5176\u4ed6\u91cd\u70b9\u8003\u70b9
\u00a0\u00a0 \u251c\u2500 DFD\u6570\u636e\u6d41\u56fe
\u00a0\u00a0 \u251c\u2500 \u5b8c\u6574\u6027\u7ea6\u675f\uff08\u5b9e\u4f53\/\u53c2\u7167\/\u7528\u6237\u5b9a\u4e49\uff09

\u4e8c\u3001\u6838\u5fc3\u77e5\u8bc6\u70b9\u4e0e\u793a\u4f8b<\/a>
1. <\/a>\u6570\u636e\u5e93\u57fa\u7840\u6982\u5ff5
\u6570\u636e\u5b9a\u4e49<\/strong>
\u6570\u636e\u662f\u63cf\u8ff0\u4e8b\u7269\u7684\u7b26\u53f7\u8bb0\u5f55\uff0c\u9700\u7ed3\u5408\u8bed\u4e49\u89e3\u91ca\u3002
\u793a\u4f8b<\/em>\uff1a\u5b66\u751f\u8bb0\u5f55S(\u5b66\u53f7, \u59d3\u540d, \u6027\u522b)\u4e2d\uff0c\u201c\u5b66\u53f7\u201d\u6807\u8bc6\u5b66\u751f\u552f\u4e00\u6027\uff0c\u201c\u6027\u522b\u201d\u9700\u9650\u5b9a\u4e3a\u7537\/\u5973\u3002
\u6570\u636e\u5e93\u7279\u5f81<\/strong>
\u6709\u7ec4\u7ec7\u3001\u53ef\u5171\u4eab\u3001\u4f4e\u5197\u4f59\u3001\u9ad8\u72ec\u7acb\u6027\u3002
\u5bf9\u6bd4<\/em>\uff1a\u4f20\u7edf\u6587\u4ef6\u7cfb\u7edf\u5b58\u5728\u5197\u4f59\uff08\u5982\u591a\u4e2a\u90e8\u95e8\u4fdd\u5b58\u540c\u4e00\u5458\u5de5\u4fe1\u606f\uff09\uff0c\u800c\u6570\u636e\u5e93\u96c6\u4e2d\u5b58\u50a8\u3002
2. <\/a>\u4e09\u7ea7\u6a21\u5f0f\u4e0e\u6570\u636e\u72ec\u7acb\u6027
\u4e09\u7ea7\u6a21\u5f0f\u4f5c\u7528<\/strong>
\u5c42\u7ea7
\u6a21\u5f0f\u7c7b\u578b
\u4f5c\u7528
\u7528\u6237\u7ea7
\u5916\u6a21\u5f0f
\u7528\u6237\u76f4\u63a5\u64cd\u4f5c\u7684\u6570\u636e\u89c6\u56fe\uff08\u5982\u89c6\u56fe\uff09
\u6982\u5ff5\u7ea7
\u6a21\u5f0f
\u6570\u636e\u5e93\u5168\u5c40\u903b\u8f91\u7ed3\u6784\uff08\u5982\u5173\u7cfb\u8868\uff09
\u7269\u7406\u7ea7
\u5185\u6a21\u5f0f
\u6570\u636e\u7269\u7406\u5b58\u50a8\u65b9\u5f0f\uff08\u5982\u7d22\u5f15\u3001\u5206\u533a\uff09
\u4e24\u7ea7\u6620\u50cf\u4e0e\u72ec\u7acb\u6027<\/strong>
\u5916\u6a21\u5f0f\/\u6a21\u5f0f\u6620\u50cf<\/strong>\uff1a\u4fee\u6539\u6a21\u5f0f\u4e0d\u5f71\u54cd\u5916\u6a21\u5f0f\uff08\u903b\u8f91\u72ec\u7acb\u6027\uff09\u3002
\u793a\u4f8b<\/em>\uff1a\u5b66\u751f\u8868\u65b0\u589e\u5b57\u6bb5\u5e74\u9f84\uff0c\u539f\u6709\u89c6\u56fe\u4ecd\u53ef\u7528\u3002
\u6a21\u5f0f\/\u5185\u6a21\u5f0f\u6620\u50cf<\/strong>\uff1a\u4fee\u6539\u5b58\u50a8\u7ed3\u6784\u4e0d\u5f71\u54cd\u6a21\u5f0f\uff08\u7269\u7406\u72ec\u7acb\u6027\uff09\u3002
\u793a\u4f8b<\/em>\uff1a\u5c06B+\u6811\u7d22\u5f15\u6539\u4e3a\u54c8\u5e0c\u7d22\u5f15\uff0c\u8868\u7ed3\u6784\u4e0d\u53d8\u3002
3. ER<\/a>\u56fe\u4e0e\u5173\u7cfb\u6a21\u578b\u8f6c\u6362
ER\u56fe\u5143\u7d20<\/strong>
\u5b9e\u4f53\uff08\u65b9\u5f62\uff09\uff1a\u5982\u5b66\u751f(\u5b66\u53f7, \u59d3\u540d)
\u8054\u7cfb\uff08\u83f1\u5f62\uff09\uff1a\u5b66\u751f\u4e0e\u8bfe\u7a0b\u7684M:N\u8054\u7cfb\u9009\u4fee
\u8f6c\u6362\u89c4\u5219<\/strong>
M:N\u8054\u7cfb\u9700\u8f6c\u6362\u4e3a\u72ec\u7acb\u8868\uff08\u5982\u9009\u4fee(\u5b66\u53f7, \u8bfe\u7a0b\u53f7, \u6210\u7ee9)\uff09
1:N\u8054\u7cfb\u5c06N\u7aef\u5b9e\u4f53\u7684\u4e3b\u7801\u52a0\u51651\u7aef\u5b9e\u4f53
4. <\/a>\u8303\u5f0f\u7406\u8bba\u4e0e\u51fd\u6570\u4f9d\u8d56
\u51fd\u6570\u4f9d\u8d56\u7c7b\u578b<\/strong>
\u7c7b\u578b
\u793a\u4f8b
\u8bf4\u660e
\u975e\u5e73\u51e1\u4f9d\u8d56
\u5b66\u53f7\u2192\u59d3\u540d
\u59d3\u540d\u4e0d\u5305\u542b\u5728\u5b66\u53f7\u4e2d
\u5e73\u51e1\u4f9d\u8d56
(\u5b66\u53f7, \u59d3\u540d)\u2192\u5b66\u53f7
\u53f3\u4fa7\u5c5e\u6027\u5728\u5de6\u4fa7\u96c6\u5408\u4e2d
\u5b8c\u5168\u4f9d\u8d56
(\u5b66\u53f7, \u8bfe\u7a0b\u53f7)\u2192\u6210\u7ee9
\u7f3a\u4e00\u4e0d\u53ef
\u90e8\u5206\u4f9d\u8d56
(\u5b66\u53f7, \u8bfe\u7a0b\u53f7)\u2192\u59d3\u540d\uff08\u5b66\u53f7\u53ef\u5355\u72ec\u51b3\u5b9a\u59d3\u540d\uff09
\u5bfc\u81f4\u5197\u4f59
\u8303\u5f0f\u5224\u65ad\u4e0e\u5206\u89e3<\/strong>
1NF\u21922NF<\/strong>\uff1a\u6d88\u9664\u90e8\u5206\u4f9d\u8d56
\u793a\u4f8b<\/em>\uff1aR(\u5b66\u53f7, \u8bfe\u7a0b\u53f7, \u59d3\u540d)\u5206\u89e3\u4e3a\u5b66\u751f(\u5b66\u53f7, \u59d3\u540d)\u548c\u9009\u4fee(\u5b66\u53f7, \u8bfe\u7a0b\u53f7, \u6210\u7ee9)
2NF\u21923NF<\/strong>\uff1a\u6d88\u9664\u4f20\u9012\u4f9d\u8d56
\u793a\u4f8b<\/em>\uff1aR(\u5b66\u53f7, \u73ed\u7ea7, \u73ed\u4e3b\u4efb)\u5206\u89e3\u4e3a\u73ed\u7ea7(\u73ed\u7ea7\u53f7, \u73ed\u4e3b\u4efb)\u548c\u5b66\u751f(\u5b66\u53f7, \u73ed\u7ea7\u53f7)
5. SQL<\/a>\u64cd\u4f5c\u4e0e\u590d\u6742\u67e5\u8be2
DDL\u4e0e\u7ea6\u675f<\/strong>
— \u521b\u5efa\u5458\u5de5\u8868\uff08\u542b\u9ed8\u8ba4\u503c\u3001\u5916\u952e\uff09
CREATE TABLE Employees(
\u00a0\u00a0\u00a0 empno CHAR(10) PRIMARY KEY,
\u00a0\u00a0\u00a0 empname VARCHAR2(20) NOT NULL,
\u00a0\u00a0\u00a0 sex CHAR(2) DEFAULT '\u7537',
\u00a0\u00a0\u00a0 dno CHAR(3),
\u00a0\u00a0\u00a0 FOREIGN KEY (dno) REFERENCES Dept(dno)
);
\u590d\u6742\u67e5\u8be2\u793a\u4f8b<\/strong>
— \u67e5\u8be2\u6bcf\u4e2a\u7b2c\u4e8c\u7ea7\u673a\u6784\u7684\u5458\u5de5\u6570\uff08\u673a\u6784\u540d\u79f0\uff0c\u5458\u5de5\u6570\uff09
SELECT d.dname AS \u673a\u6784\u540d\u79f0, COUNT(e.empno) AS \u5458\u5de5\u6570
FROM Dept d
JOIN Employees e ON d.dno = e.dno
WHERE d.dparent IS NOT NULL\u00a0 — \u7b2c\u4e8c\u7ea7\u673a\u6784
GROUP BY d.dname;
6. <\/a>\u4e8b\u52a1\u4e0e\u5e76\u53d1\u63a7\u5236
ACID\u7279\u6027<\/strong>
\u539f\u5b50\u6027<\/strong>\uff1a\u4e8b\u52a1\u8981\u4e48\u5168\u505a\uff0c\u8981\u4e48\u5168\u4e0d\u505a\uff08\u5982\u8f6c\u8d26\u64cd\u4f5c\uff09\u3002
\u9694\u79bb\u6027<\/strong>\uff1a\u901a\u8fc7\u9501\u673a\u5236\u907f\u514d\u810f\u8bfb\uff08\u5982SELECT … FOR UPDATE\uff09\u3002
\u65e5\u5fd7\u4e0e\u6062\u590d<\/strong>
UNDO<\/strong>\uff1a\u56de\u6eda\u672a\u63d0\u4ea4\u4e8b\u52a1\uff08\u5982\u7cfb\u7edf\u5d29\u6e83\u65f6\uff09\u3002
REDO<\/strong>\uff1a\u91cd\u505a\u5df2\u63d0\u4ea4\u4e8b\u52a1\uff08\u5982\u65ad\u7535\u540e\u6062\u590d\uff09\u3002

\u4e09\u3001\u7ec3\u4e60\u9898\u4e0e\u7b54\u6848<\/a>
\u9898\u76ee1<\/a>\uff1a\u8303\u5f0f\u5224\u65ad\u4e0e\u5206\u89e3
\u8981\u6c42<\/strong>\uff1a
\u5173\u7cfb\u6a21\u5f0fR(\u961f\u5458\u7f16\u53f7, \u6bd4\u8d5b\u573a\u6b21, \u8fdb\u7403\u6570, \u7403\u961f\u540d, \u961f\u957f\u540d)\uff0c\u6bcf\u4e2a\u961f\u5458\u4ec5\u5c5e\u4e00\u4e2a\u7403\u961f\uff0c\u6bcf\u961f\u53ea\u6709\u4e00\u4e2a\u961f\u957f\u3002
\u5199\u51fa\u51fd\u6570\u4f9d\u8d56
\u786e\u5b9a\u5019\u9009\u7801
\u5224\u65ad\u6700\u9ad8\u8303\u5f0f\u7ea7\u522b
\u7b54\u6848<\/strong>\uff1a
\u51fd\u6570\u4f9d\u8d56\uff1a
\u961f\u5458\u7f16\u53f7\u2192\u7403\u961f\u540d
\u7403\u961f\u540d\u2192\u961f\u957f\u540d
(\u961f\u5458\u7f16\u53f7, \u6bd4\u8d5b\u573a\u6b21)\u2192\u8fdb\u7403\u6570
\u5019\u9009\u7801\uff1a(\u961f\u5458\u7f16\u53f7, \u6bd4\u8d5b\u573a\u6b21)
\u6700\u9ad8\u8303\u5f0f\uff1a2NF\uff08\u5b58\u5728\u4f20\u9012\u4f9d\u8d56\u961f\u5458\u7f16\u53f7\u2192\u7403\u961f\u540d\u2192\u961f\u957f\u540d\uff09
\u7c7b\u4f3c\u9898\u76ee<\/strong>\uff1a
\u5173\u7cfb\u6a21\u5f0fR(S#, C#, G, T#)\uff08S#: \u5b66\u53f7, C#: \u8bfe\u7a0b\u53f7, G: \u6210\u7ee9, T#: \u6559\u5e08\u53f7\uff09\uff0c\u82e5S# \u2192 T#\uff0c\u5224\u65ad\u8303\u5f0f\u7ea7\u522b\u3002
\u7b54\u6848<\/strong>\uff1a2NF\uff08\u5b58\u5728\u4f20\u9012\u4f9d\u8d56\uff0cS# \u2192 T#\u4f46\u975e\u4e3b\u5c5e\u6027\u4f9d\u8d56\u4e3b\u7801\uff09\u3002

\u9898\u76ee2<\/a>\uff1aER\u56fe\u8f6c\u6362
\u8981\u6c42<\/strong>\uff1a
\u5546\u4e1a\u96c6\u56e2\u6570\u636e\u5e93\u5305\u542b\u5546\u5e97\u3001\u5546\u54c1\u3001\u804c\u5de5\u5b9e\u4f53\uff0c\u4ee5\u53ca\u9500\u552e\uff08M:N\uff09\u548c\u8058\u7528\uff081:N\uff09\u8054\u7cfb\u3002
\u7ed8\u5236ER\u56fe
\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\u5e76\u6807\u51fa\u4e3b\u7801
\u7b54\u6848<\/strong>\uff1a
ER\u56fe\u5143\u7d20\uff1a
\u5b9e\u4f53\uff1a\u5546\u5e97\uff08\u5546\u5e97\u7f16\u53f7, \u5546\u5e97\u540d, \u5730\u5740\uff09
\u5546\u54c1\uff08\u5546\u54c1\u53f7, \u5546\u54c1\u540d, \u89c4\u683c, \u5355\u4ef7\uff09
\u804c\u5de5\uff08\u804c\u5de5\u7f16\u53f7, \u59d3\u540d, \u6027\u522b, \u4e1a\u7ee9\uff09
\u8054\u7cfb\uff1a\u9500\u552e\uff08\u6708\u9500\u552e\u91cf\uff09\u3001\u8058\u7528\uff08\u8058\u671f, \u5de5\u8d44\uff09
\u5173\u7cfb\u6a21\u5f0f\uff1a
\u5546\u5e97(\u5546\u5e97\u7f16\u53f7, \u5546\u5e97\u540d, \u5730\u5740)
\u5546\u54c1(\u5546\u54c1\u53f7, \u5546\u54c1\u540d, \u89c4\u683c, \u5355\u4ef7)
\u9500\u552e(\u5546\u5e97\u7f16\u53f7, \u5546\u54c1\u53f7, \u6708\u9500\u552e\u91cf) \u4e3b\u7801\uff1a(\u5546\u5e97\u7f16\u53f7, \u5546\u54c1\u53f7)
\u804c\u5de5(\u804c\u5de5\u7f16\u53f7, \u59d3\u540d, \u6027\u522b, \u4e1a\u7ee9, \u5546\u5e97\u7f16\u53f7, \u8058\u671f, \u5de5\u8d44) \u4e3b\u7801\uff1a\u804c\u5de5\u7f16\u53f7
\u7c7b\u4f3c\u9898\u76ee<\/strong>\uff1a
\u516c\u4ea4\u516c\u53f8\u6570\u636e\u5e93\u5305\u542b\u5458\u5de5\u8868\u548c\u7ec4\u7ec7\u673a\u6784\u8868\uff0c\u7ed8\u5236ER\u56fe\u5e76\u8f6c\u6362\u4e3a\u5173\u7cfb\u6a21\u5f0f\u3002
\u7b54\u6848<\/strong>\uff1a
\u5458\u5de5\u8868(Employees): empno, empname, age, sex, dno
\u7ec4\u7ec7\u673a\u6784\u8868(Dept): dno, dname, dleader, dparent
\u5173\u7cfb\uff1a\u5458\u5de5\u5c5e\u4e8e\u673a\u6784\uff08\u5916\u952eEmployees.dno \u2192 Dept.dno\uff09

\u9898\u76ee<\/a>3\uff1aSQL\u67e5\u8be2\u4e0e\u5173\u7cfb\u4ee3\u6570
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SQL\u67e5\u8be2\uff1a
SELECT d.dname AS \u673a\u6784\u540d\u79f0, COUNT(e.empno) AS \u5458\u5de5\u6570
FROM Dept d
JOIN Employees e ON d.dno = e.dno
WHERE d.dparent IS NOT NULL\u00a0 — \u7b2c\u4e8c\u7ea7\u673a\u6784
GROUP BY d.dname;
\u5173\u7cfb\u4ee3\u6570\uff1a
\u03c3(age > 35 \u2227 sex = '\u7537')(Employees)
\u7c7b\u4f3c\u9898\u76ee<\/strong>\uff1a
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\u7b54\u6848<\/strong>\uff1a
\u03c0(dname)(\u03c3(empname = '\u674e\u654f')(Employees \u22c8 Dept))

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\u8981\u6c42<\/strong>\uff1a
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BCNF<\/strong>\uff1a\u6240\u6709\u51b3\u5b9a\u56e0\u7d20\u662f\u5019\u9009\u7801\u7684\u8303\u5f0f\u3002
2. <\/a>\u7b80\u7b54\u9898\uff08\u4f8b\u9898\uff09
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3. <\/a>\u5e94\u7528\u9898\uff08\u4f8b\u9898\uff09
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\u8303\u5f0f\u5206\u89e3<\/strong>\uff1a\u5c06R(S#, C#, G, T#)\u5206\u89e3\u4e3a3NF
4. <\/a>\u8ba1\u7b97\u9898\uff08\u4f8b\u9898\uff09
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\u4e94\u3001\u590d\u4e60\u7b56\u7565<\/a>
SQL\u5f3a\u5316<\/strong>\uff1a\u6bcf\u65e5\u7ec3\u4e60\u590d\u6742\u67e5\u8be2\uff08\u591a\u8868\u8fde\u63a5+GROUP BY+HAVING\uff09\u3002
\u8303\u5f0f\u8bad\u7ec3<\/strong>\uff1a\u901a\u8fc7\u6848\u4f8b\u5224\u65ad\u8303\u5f0f\u7ea7\u522b\u5e76\u8fdb\u884c\u89c4\u8303\u5316\u5206\u89e3\u3002
ER\u56fe\u5b9e\u6218<\/strong>\uff1a\u9488\u5bf9\u201c\u5b66\u751f\u9009\u8bfe\u201d\u201c\u56fe\u4e66\u7ba1\u7406\u201d\u7b49\u573a\u666f\u7ed8\u5236ER\u56fe\u3002
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SQL\u67e5\u8be2\u4e0e\u64cd\u4f5c\u00a0\u00a0 \u251c\u2500 DDL\/DML\/DCL\/TCL\u57fa\u7840\u8bed\u6cd5\u00a0\u00a0 \u251c\u2500 \u590d\u6742\u67e5\u8be2\uff08\u591a\u8868\u8fde\u63a5\u3001\u5b50\u67e5\u8be2\u3001\u805a\u5408\u51fd\u6570\uff09\u00a0\u00a0 \u251c\u2500 \u5173\u7cfb\u4ee3\u6570\u8fd0\u7b97\uff08\u9009\u62e9\/\u6295\u5f71\/\u8fde\u63a5\/\u9664\u6cd5\uff095. \u4e8b\u52a1\u4e0e\u5e76\u53d1\u63a7\u5236\u00a0\u00a0 \u251c\u2500 ACID\u7279\u6027\u4e0e\u9501\u673a\u5236\u00a0\u00a0 \u251c\u2500 \u65e5\u5fd7\u4e0e\u6062\u590d\u7b56\u7565\uff08UNDO\/REDO\uff096. \u5176\u4ed6\u91cd\u70b9\u8003\u70b9\u00a0\u00a0 \u251c\u2500 DFD\u6570\u636e\u6d41\u56fe\u00a0\u00a0 \u251c\u2500 \u5b8c\u6574\u6027\u7ea6\u675f\uff08\u5b9e\u4f53\/\u53c2\u7167\/\u7528\u6237\u5b9a\u4e49\uff09 \u4e8c\u3001\u6838\u5fc3\u77e5\u8bc6\u70b9\u4e0e\u793a\u4f8b1. \u6570\u636e\u5e93\u57fa\u7840\u6982\u5ff5\u6570\u636e\u5b9a\u4e49\u6570\u636e\u662f\u63cf\u8ff0\u4e8b\u7269\u7684\u7b26\u53f7\u8bb0\u5f55\uff0c\u9700\u7ed3\u5408\u8bed\u4e49\u89e3\u91ca\u3002\u793a\u4f8b\uff1a\u5b66\u751f\u8bb0\u5f55S(\u5b66\u53f7, \u59d3\u540d, \u6027\u522b)\u4e2d\uff0c\u201c\u5b66\u53f7\u201d\u6807\u8bc6\u5b66\u751f\u552f\u4e00\u6027\uff0c\u201c\u6027\u522b\u201d\u9700\u9650\u5b9a\u4e3a\u7537\/\u5973\u3002\u6570\u636e\u5e93\u7279\u5f81\u6709\u7ec4\u7ec7\u3001\u53ef\u5171\u4eab\u3001\u4f4e\u5197\u4f59\u3001\u9ad8\u72ec\u7acb\u6027\u3002\u5bf9\u6bd4\uff1a\u4f20\u7edf\u6587\u4ef6\u7cfb\u7edf\u5b58\u5728\u5197\u4f59\uff08\u5982\u591a\u4e2a\u90e8\u95e8\u4fdd\u5b58\u540c\u4e00\u5458\u5de5\u4fe1\u606f\uff09\uff0c\u800c\u6570\u636e\u5e93\u96c6\u4e2d\u5b58\u50a8\u30022. \u4e09\u7ea7\u6a21\u5f0f\u4e0e\u6570\u636e\u72ec\u7acb\u6027\u4e09\u7ea7\u6a21\u5f0f\u4f5c\u7528\u5c42\u7ea7\u6a21\u5f0f\u7c7b\u578b\u4f5c\u7528\u7528\u6237\u7ea7\u5916\u6a21\u5f0f\u7528\u6237\u76f4\u63a5\u64cd\u4f5c\u7684\u6570\u636e\u89c6\u56fe\uff08\u5982\u89c6\u56fe\uff09\u6982\u5ff5\u7ea7\u6a21\u5f0f\u6570\u636e\u5e93\u5168\u5c40\u903b\u8f91\u7ed3\u6784\uff08\u5982\u5173\u7cfb\u8868\uff09\u7269\u7406\u7ea7\u5185\u6a21\u5f0f\u6570\u636e\u7269\u7406\u5b58\u50a8\u65b9\u5f0f\uff08\u5982\u7d22\u5f15\u3001\u5206\u533a\uff09\u4e24\u7ea7\u6620\u50cf\u4e0e\u72ec\u7acb\u6027\u5916\u6a21\u5f0f\/\u6a21\u5f0f\u6620\u50cf\uff1a\u4fee\u6539\u6a21\u5f0f\u4e0d\u5f71\u54cd\u5916\u6a21\u5f0f\uff08\u903b\u8f91\u72ec\u7acb\u6027\uff09\u3002\u793a\u4f8b\uff1a\u5b66\u751f\u8868\u65b0\u589e\u5b57\u6bb5\u5e74\u9f84\uff0c\u539f\u6709\u89c6\u56fe\u4ecd\u53ef\u7528\u3002\u6a21\u5f0f\/\u5185\u6a21\u5f0f\u6620\u50cf\uff1a\u4fee\u6539\u5b58\u50a8\u7ed3\u6784\u4e0d\u5f71\u54cd\u6a21\u5f0f\uff08\u7269\u7406\u72ec\u7acb\u6027\uff09\u3002\u793a\u4f8b\uff1a\u5c06B+\u6811\u7d22\u5f15\u6539\u4e3a\u54c8\u5e0c\u7d22\u5f15\uff0c\u8868\u7ed3\u6784\u4e0d\u53d8\u30023. 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