Oracle Rownum 函数在复杂查询中的使用技巧主要有以下几点:
SELECT *
FROM (
SELECT *
FROM table_name
WHERE conditions
ORDER BY column_name
)
WHERE ROWNUM <= 10;
SELECT *
FROM (
SELECT DISTINCT *
FROM table_name
WHERE conditions
)
WHERE ROWNUM <= 10;
SELECT *
FROM (
SELECT *
FROM table_name
WHERE conditions
ORDER BY column_name
)
WHERE ROWNUM <= 10;
SELECT *
FROM table_name
WHERE MOD(ROWNUM, 2) = 1;
总的来说,Oracle Rownum 函数在复杂查询中的使用技巧可以帮助我们更灵活地进行数据操作和查询,提高查询效率和准确性。
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