由于“insert into 语句中的语法错误”，我的输出没有进入数据库

问题描述

public static void main(String[] args) {
    int unitPrintMarksTotal = 0;
    for (int i = 0; i < 10000; i++) {
        unitPrintMarksTotal += generateBatchOfUniquePrintMarks(i);
    }

    System.out.println("The precision across 10000 runs with 100 item batches is: " + (float) unitPrintMarksTotal / 10000);
}

private static int generateBatchOfUniquePrintMarks(int batch) {
    Set<String> printMarks = new HashSet<>();
    for (int i = 0; i < 100; i++) {
        printMarks.add(generatePrintMarkWithJavaUtil());
    }

    System.out.println("Batch " + batch + " Unique number of elements is " + printMarks.size());

    return printMarks.size();
}

// the best so far => 98.65
// with 3 chars => 99.98
// with 4 chars => 99.9997
private static String generatePrintMarkWithJavaUtil() {
    int leftLimit = 48; // numeral '0'
    int rightLimit = 122; // letter 'z'
    int targetStringLength = 2;
    String printMark;
    do {
        printMark = new Random().ints(leftLimit,rightLimit + 1)
                .filter(i -> (i <= 57 || i >= 65) && (i <= 90 || i >= 97))
                .limit(targetStringLength)
                .collect(StringBuilder::new,StringBuilder::appendCodePoint,StringBuilder::append)
                .toString();
    } while (!isValid(printMark));

    return printMark;
}

// 95.46
private static String generatePrintMarkWithCommonsLang3() {
    String printMark;
    do {
        printMark = RandomStringUtils.randomAlphanumeric(2).toupperCase();
    } while (!isValid(printMark));

    return printMark;
}

// 95.92
private static String generatePrintMarkWithMathRandom() {
    final String ALPHA_NUMERIC_STRING = "ABCDEFGHIJKLMnopQRSTUVWXYZ0123456789";
    StringBuilder printMark;
    do {
        printMark = new StringBuilder();
        int i = (int) (Math.random() * ALPHA_NUMERIC_STRING.length());
        printMark.append(ALPHA_NUMERIC_STRING.charat(i));
        int j = (int) (Math.random() * ALPHA_NUMERIC_STRING.length());
        printMark.append(ALPHA_NUMERIC_STRING.charat(j));
    } while (!isValid(printMark.toString()));

    return printMark.toString();
}

private static boolean isValid(final String printMark) {
    return true;
}

解决方法

CONNECT 是一个 Access database engine reserved word

将方括号括起来，它应该可以工作。

Insert into [connect] ([jersey],[Fname],[Mname],[Lname]) Values (?,?,?)