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Oracle-CheatSheet

返回目录

Oracle CheatSheet

Query

  • 获取前 N 行

SELECT val
FROM rownum_order_test
ORDER BY val DESC
FETCH FIRST 5 ROWS ONLY;
  • 获取前 N 行,如果第 N 行有多个相同值,则全部返回

SELECT val
FROM rownum_order_test
ORDER BY val DESC
FETCH FIRST 5 ROWS WITH TIES;
  • 获取前 x% 行:

SELECT val
FROM rownum_order_test
ORDER BY val
FETCH FIRST 20 PERCENT ROWS ONLY;
  • 根据偏移量查询,适用于需要分页的情况:

SELECT val
FROM rownum_order_test
ORDER BY val
OFFSET 4 ROWS FETCH NEXT 4 ROWS ONLY;
  • 综合使用偏移量与百分比查询:

SELECT val
FROM rownum_order_test
ORDER BY val
OFFSET 4 ROWS FETCH NEXT 20 PERCENT ROWS ONLY;