代码
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import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.math.BigDecimal;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;
import java.util.Objects;
public class 大数据导出为insert {
public static Mysql8Instance m;
public static List<String> tables = new ArrayList<>();
private static Integer onCount = 10000;
public static String search = "";
public static void main(String[] args) throws Exception {
大数据导出为insert t = new 大数据导出为insert();
t.m = new Mysql8Instance("127.0.0.1", 3306, "test", "root", "123456");
t.m.setReturnColumnName(true);
t.tables.add("test");
t.search = " where 1=1 ";
t.handle();
}
public static void handle() throws Exception {
long t = System.currentTimeMillis();
long totals = 0;
for (String table : tables) {
long currentTimeMillis = System.currentTimeMillis();
File file = new File(table + ".sql");
// TODO 先删除再创建文件，避免文件有其他内容
file.delete();
file.createNewFile();
BufferedWriter output = new BufferedWriter(new FileWriter(file, true));// true,则追加写入text文本
// 字段
List<List<String>> fs = m.query("select\n" +
"column_name from information_schema.columns\n" +
"where table_schema = '" + m.getDatabase() + "'\n" +
"and table_name = '" + table + "' ; ");
fs.remove(0);
StringBuffer fileds = new StringBuffer();
for (List<String> f : fs) {
fileds.append("`").append(f.get(0)).append("`,");
}
fileds.delete(fileds.length() - 1, fileds.length());
String title = "insert into `" + m.getDatabase() + "`.`" + table + "` (" + fileds + ")values ";
// 内容
long total = 0;
int start = 0;
List<List<String>> rs;
while ((rs = getData(m, "SELECT " + fileds + " FROM " + table + " " + search + " limit " + start + "," + onCount)).size() > 1) {
rs.remove(0);
System.out.println("导出数据 ,limit:[" + start + "," + onCount + "]");
List<List<List<String>>> lists = null;
if (rs.size() > 900) {
lists = averageAssign(rs, 900);
} else {
lists = new ArrayList<>();
lists.add(rs);
}
for (List<List<String>> list : lists) {
output.write(title);
output.write("\r\n");// 换行
for (int i = 0; i < list.size(); i++) {
StringBuffer c = new StringBuffer();
for (String s : list.get(i)) {
if (s == null) {
c.append("null,");
} else {
c.append("'").append(s).append("',");
}
}
c.delete(c.length() - 1, c.length());
output.write("(" + c + ")");
if (i == (list.size() - 1)) {
output.write(";\r\n");// 换行
} else {
output.write(",\r\n");// 换行
}
}
}
total += rs.size();
start += onCount;
}
output.flush();
output.close();
totals += total;
System.out.println("[" + table + "]数据导出完成,数据量:" + total + ", 耗时:" + getHaoShi(System.currentTimeMillis() - currentTimeMillis));
}
m.close();
System.out.println("所有表数据导出完成,表数:" + tables.size() + ",总数量:" + totals + ", 耗时:" + getHaoShi(System.currentTimeMillis() - t));
}
public static List<List<String>> getData(Mysql8Instance m, String sql) {
return m.query(sql);
}
public static <T> List<List<T>> averageAssign(List<T> source, int n) {
List<List<T>> result = new ArrayList<List<T>>();
int remainder = source.size() % n; //先计算出余数
int number = source.size() / n; //然后是商
int offset = 0;//偏移量（用以标识加的余数）
for (int i = 0; i < n; i++) {
List<T> value;
if (remainder > 0) {
value = source.subList(i * number + offset, (i + 1) * number + offset + 1);
remainder--;
offset++;
} else {
value = source.subList(i * number + offset, (i + 1) * number + offset);
}
result.add(value);
}
return result;
}
/**
* 计算耗时
*
* @param t 毫秒
* @return
*/
public static String getHaoShi(double t) {
double d7 = t / 1000.0 / 60 / 60 / 24 / 30 / 12 / 100;
if (d7 > 1) return round(d7, 1) + "纪元";
double d6 = t / 1000.0 / 60 / 60 / 24 / 30 / 12;
if (d6 > 1) return round(d6, 1) + "年";
double d5 = t / 1000.0 / 60 / 60 / 24 / 30;
if (d5 > 1) return round(d5, 1) + "月";
double d4 = t / 1000.0 / 60 / 60 / 24;
if (d4 > 1) return round(d4, 1) + "天";
double d3 = t / 1000.0 / 60 / 60;
if (d3 > 1) return round(d3, 1) + "小时";
double d2 = t / 1000.0 / 60;
if (d2 > 1) return round(d2, 1) + "分钟";
double d1 = t / 1000.0;
if (d1 > 1) return round(d1, 1) + "秒";
return t + "毫秒";
}
public static String join(List<String> list, String separator) {
Iterator<String> iterator = list.iterator();
if (iterator == null) {
return null;
} else if (!iterator.hasNext()) {
return "";
} else {
Object first = iterator.next();
if (!iterator.hasNext()) {
return Objects.toString(first, "");
} else {
StringBuilder buf = new StringBuilder(256);
if (first != null) {
buf.append(first);
}
while (iterator.hasNext()) {
if (separator != null) {
buf.append(separator);
}
Object obj = iterator.next();
if (obj != null) {
buf.append(obj);
}
}
return buf.toString();
}
}
}
public static Double round(Double data, int amount) {
if (data == null)
return null;
//利用BigDecimal来实现四舍五入.保留一位小数
double result = new BigDecimal(data).setScale(amount, BigDecimal.ROUND_HALF_UP).doubleValue();
//1代表保留1位小数,保留两位小数就是2,依此累推
//BigDecimal.ROUND_HALF_UP 代表使用四舍五入的方式
return result;
}
/**
CREATE TABLE test.`test1` (
`pkid` bigint NOT NULL AUTO_INCREMENT COMMENT '主键id',
`sys_create_time` datetime DEFAULT NULL COMMENT '创建时间',
`sys_modify_time` datetime DEFAULT NULL COMMENT '修改时间',
`lng` double DEFAULT NULL COMMENT '经度',
`name` varchar(100) DEFAULT NULL COMMENT '名称',
`time` bigint DEFAULT NULL COMMENT '时间',
`age` varchar(100) DEFAULT NULL COMMENT '年龄',
`speed` double DEFAULT NULL COMMENT '速度',
`lat` double DEFAULT NULL COMMENT '维度',
`sdate` int(11) NOT NULL COMMENT '小时(分区键)',
PRIMARY KEY (`pkid`,`sdate`)
) ENGINE=InnoDB DEFAULT CHARSET=utf8 COMMENT='测试表1';
*/
}
Mysql8Instance类如下
mysql(30) : java管理mysql8(开发用轻量版)_java mysql8-CSDN博客