子字符串 substring

子字符串须相符 match substring

子字符串及集合的元素 SUBSTRING AND ELEMENTS FROM SET

子字符串函数 Left Mid Right ; SUBSTR ; Vocational Education Research

取子字符串 substring

原子字符边界 atomic character boundary

电子字符读出 [计] electronic character sensing

替换子字符串 Replace Substring ; Replacing Substrings

原子字符串 string atoms