Learning bLog

I tried one query (originally asked at JR) on MySQL which export the table data into a file, with a comma delimited field. The query is straight forward and replace the null column value by "\N" character, but when I want to replace that "\N" value by some other character like "0" or simple empty field like " ", its gets little tricky. Here is the base query SELECT Id, name, age FROM student INTO OUTFILE 'c:/result.txt' FIELDS TERMINATED BY ',' OPTIONALLY ENCLOSED BY '"' LINES TERMINATED BY '\n'; And it outputs like, 1, "sagar", 23 2, "anant", 24 Now suppose some 'name' fields are null, then it outputs like 1, "sagar", 23 2, \N, 24 Now to obtain my desired results, which replace this null (\N) values by empty string like, "", I tried out two solutions --1. Using CASE statement SELECT Id, CASE WHEN name IS NULL THEN '' ELSE name END AS NewName, age FROM s...

com.mysql.jdbc.CommunicationsException: Communications link failure due to underlying exception: ** BEGIN NESTED EXCEPTION ** java.net.SocketException MESSAGE: Software caused connection abort: recv failed STACKTRACE: java.net.SocketException: Software caused connection abort: recv failed Environment: Apache Tomcat 6.0.14 with MySQL 5.2 This is the exception which was the night mare for many developers who used MySQL with Java Web application in Tomcat server. Before explaining the cause let me told you that, the exception has responsible for pulling my hair for almost 2 weeks, with little use of Googling and MySQL Forum! Particularly, the problem was, I lost my connection object when server is idle for 24 to 34 hours, so any request comes after this time interval results in above exception. Disclaimer: The below explanation is as per my understanding and as I’m not an architecture of MySQL JConnector nor Apache DBCP API, Comments & Suggestions are welcomed, See this link from wh...