我很想知道,如果第一个特定领域空空空空的话,能否掌握能够选择替代领域的我的智慧。
例:我有表格,称“内部”和“连续”的“职位”。 在同一个发言中,如果“内部”是空洞的,但并非结果阵列,我要选择“连续”。
预 收
共同点是你们所期待的。
SELECT COALESCE(intro, content) AS column1
FROM table
假设无所作为,而不是长足。
有两个潜在途径。 具体案情陈述。
Select case when field1 <> then field2 else field1 end
或您可以使用香料。
select coalesce(field1, field2)
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