You cannot drop column directly from a table using command ALTER TABLE table_name drop col_name; The only way to drop column is using replace command. Lets say, I have a table emp with id, name and dept column. I want to drop id column of table emp. So provide all those columns which you want … Read more
datediff(to_date(String timestamp), to_date(String timestamp)) For example: SELECT datediff(to_date(‘2019-08-03’), to_date(‘2019-08-01’)) <= 2;
tblproperties will give the size of the table and can be used to grab just that value if needed. — gives all properties show tblproperties yourTableName — show just the raw data size show tblproperties yourTableName(“rawDataSize”)
regexp_replace UDF performs my task. Below is the definition and usage from apache Wiki. regexp_replace(string INITIAL_STRING, string PATTERN, string REPLACEMENT): This returns the string resulting from replacing all substrings in INITIAL_STRING that match the java regular expression syntax defined in PATTERN with instances of REPLACEMENT, e.g.: regexp_replace(“foobar”, “oo|ar”, “”) returns fb
There is no surety if pig uses the configuration DEFAULT_PARALLEL value for every steps in the pig script. Try PARALLEL along with your specific join/group step which you feel taking time (In your case GROUP step). inputDataGrouped = GROUP inputData BY (group_name) PARALLEL 67; If still it is not working then you might have to … Read more
The problem connecting recource manager was because ive needed to add a few properties to yarn-site.xml : <property> <name>yarn.resourcemanager.address</name> <value>127.0.0.1:8032</value> </property> <property> <name>yarn.resourcemanager.scheduler.address</name> <value>127.0.0.1:8030</value> </property> <property> <name>yarn.resourcemanager.resource-tracker.address</name> <value>127.0.0.1:8031</value> </property> Yet, my Jobs arent runing but connecting is successful now
This error is caused by the block replication system of HDFS since it could not manage to make any copies of a specific block within the focused file. Common reasons of that: Only a NameNode instance is running and it’s not in safe-mode There is no DataNode instances up and running, or some are dead. … Read more
No, there is no other option to sort the files based on datetime. If you are using hadoop version < 2.7, you will have to use sort -k6,7 as you are doing: hdfs dfs -ls /tmp | sort -k6,7 And for hadoop 2.7.x ls command , there are following options available : Usage: hadoop fs … Read more