replace(X,Y,Z) The replace(X,Y,Z) function returns a string formed by substituting string Z for every occurrence of string Y in string X. The BINARY collating sequence is used for comparisons. If Y is an empty string then return X unchanged. If Z is not initially a string, it is cast to a UTF-8 string prior to processing.
x:要处理的字符串
y:被替换的字符串
z:替换后的字符串
有图有真相
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