向資料庫中批量插入大量資料
阿新 • • 發佈:2020-12-25
1. addBatch(sql)
Class.forName("com.mysql.jdbc.Driver");//指定連線型別 Connection con = DriverManager.getConnection(url, username, password); PreparedStatement pst = con.prepareStatement(""); for (int i = 0; i < 10; i++) { StringBuilder sql = new StringBuilder(); sql.append("INSERT INTO extenal_studentcj(grade,clazz,zkzh,NAME,scoretext,times) VALUES("); sql.append("'").append(i).append("',"); sql.append("'").append(i).append("',"); sql.append("'").append(i).append("',"); sql.append("'").append(i).append("',"); sql.append("'").append(i).append("',"); sql.append("'").append(i).append("'"); sql.append(");"); pst.addBatch(sql.toString()); } pst.executeBatch(); pst.close(); con.close();
2. addBatch()
Class.forName("com.mysql.jdbc.Driver");//指定連線型別 Connection con = DriverManager.getConnection(url, username, password); String sql = "INSERT INTO extenal_studentcj(grade,clazz,zkzh,NAME,scoretext,times) VALUES(?,?,?,?,?,?)"; PreparedStatement pst = con.prepareStatement(sql); for (int i = 0; i < 10; i++) { int idx = 1; pst.setString(idx++, i + ""); pst.setString(idx++, i + ""); pst.setString(idx++, i + ""); pst.setString(idx++, i + ""); pst.setString(idx++, i + ""); pst.setLong(idx++, i); pst.addBatch(); } pst.executeBatch(); pst.close(); con.close();
後來才發現要批量執行的話,JDBC連線URL字串中需要新增一個引數:rewriteBatchedStatements=true
例如:jdbc:mysql://127.0.0.1:8080/xihudb?rewriteBatchedStatements=true
沒有 rewriteBatchedStatements=true 則都是forEach. 開啟後 addBatch(),addBatch(sql)使用的都是一次傳送
3. 拼接SQL語句
拼接SQL
<insert id="insert" parameterType="com.Info"> insert into pp (str1, str2) values <foreach collection="ps" item="p" separator=","> (#{p.str1,jdbcType=VARCHAR}, #{p.str2,jdbcType=VARCHAR}, </foreach> </insert>
三者之間的相對速度比較:
JDBC BATCH(1)> Mybatis BATCH(2) > 拼接SQL(4)