private String buildUpdateConnection(String[] fieldNames, String[] uniqueKeyFields, boolean allReplace) {
        List<String> uniqueKeyList = Arrays.asList(uniqueKeyFields);
        return Arrays.stream(fieldNames)
                .filter(col -> !uniqueKeyList.contains(col))
                .map(col -> buildConnectString(allReplace, col))
                .collect(Collectors.joining(","));
    }
build    T1."A"=T2."A" or  T1."A"=nvl(T2."A",T1."A")
@param fieldNames
@param uniqueKeyFields
@param allReplace
@return
db2/db2-sink/src/main/java/com/dtstack/flink/sql/sink/db/DbDialect.java