COLLATE 節は優先順位が高い（||
よりも上）ので、式
x || y COLLATE z
は以下と同じ意味になります。
x || (y COLLATE z)
This is a translation of the MySQL Reference Manual that can be found at dev.mysql.com. The original Reference Manual is in English, and this translation is not necessarily as up to date as the English version.
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