How we can access the tracking URL logs. Getting error while accessing logs. http://cxln2.c.thelab-240901.internal:8088/proxy/application_1573919454381_2611/
Sqoop - Resources slide no 11. I think, there is mistake, In sqoop export command, There should be /apps/hive/warehouse/sg.db/sales_test instead of /apps/hive/warehouse/sales_test.
Let me if the following from sqoop manual is not clear. I will write in more details:
"Since Sqoop breaks down export process into multiple transactions, it is possible that a failed export job may result in partial data being committed to the database. This can further lead to subsequent jobs failing due to insert collisions in some cases, or lead to duplicated data in others. You can overcome this problem by specifying a staging table via the --staging-table option which acts as an auxiliary table that is used to stage exported data. The staged data is finally moved to the destination table in a single transaction.
In order to use the staging facility, you must create the staging table prior to running the export job. This table must be structurally identical to the target table. This table should either be empty before the export job runs, or the --clear-staging-table option must be specified. If the staging table contains data and the --clear-staging-table option is specified, Sqoop will delete all of the data before starting the export job."
ArgumentDescription --class-name <class>Specify the name of the record-specific class to use during the merge job. --jar-file <file>Specify the name of the jar to load the record class from. --merge-key <col>Specify the name of a column to use as the merge key. --new-data <path>Specify the path of the newer dataset. --onto <path>Specify the path of the older dataset. --target-dir <path>Specify the target path for the output of the merge job.
The merge tool runs a MapReduce job that takes two directories as input: a newer dataset, and an older one. These are specified with --new-data and --onto respectively. The output of the MapReduce job will be placed in the directory in HDFS specified by --target-dir.
When merging the datasets, it is assumed that there is a unique primary key value in each record. The column for the primary key is specified with --merge-key. Multiple rows in the same dataset should not have the same primary key, or else data loss may occur.
To parse the dataset and extract the key column, the auto-generated class from a previous import must be used. You should specify the class name and jar file with --class-name and --jar-file. If this is not availab,e you can recreate the class using the codegen tool.
The merge tool is typically run after an incremental import with the date-last-modified mode (sqoop import --incremental lastmodified …).
Supposing two incremental imports were performed, where some older data is in an HDFS directory named older and newer data is in an HDFS directory named newer, these could be merged like so:
$ sqoop merge --new-data newer --onto older --target-dir merged \ --jar-file datatypes.jar --class-name Foo --merge-key id This would run a MapReduce job where the value in the id column of each row is used to join rows; rows in the newer dataset will be used in preference to rows in the older dataset.
This can be used with both SequenceFile-, Avro- and text-based incremental imports. The file types of the newer and older datasets must be the same.
The eval command executes whatever sql you provide the database. This can be any sql command. For example: $ sqoop eval --connect jdbc:mysql://c.cloudxlab.com/sqo... --username sqoopuser -e “select * from widgets”
Sqoop Lab : Hi , I am trying to filter the data before importing in HDFS using sqoop CLI, However filteration using --where or Query is not getting considered. I can see entire getting imported. Please correct me in case of any error in command?
Command used :
sqoop import --connect jdbc:mysql://ip-172-31-13-154/retail_db --username sqoopuser -p --table products --query "select * from products where product_category_id > 50 "
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18 Comments
How we can access the tracking URL logs. Getting error while accessing logs.
Upvote Sharehttp://cxln2.c.thelab-240901.internal:8088/proxy/application_1573919454381_2611/
Hello,
Upvote ShareOnly basic parts/things are covered in the sqoop, It'd better if you cover advance topics in details.
Sure thanks for the feedback
Upvote ShareSqoop - Resources
Upvote Shareslide no 11. I think, there is mistake, In sqoop export command, There should be /apps/hive/warehouse/sg.db/sales_test instead of /apps/hive/warehouse/sales_test.
Can i import data from my local database to cloubxlab hdfs using sqoob?
Upvote ShareWhat is the functionality of --clear-staging-table option in the sqoop import command?
Upvote ShareCan somebody help?
Upvote ShareLet me if the following from sqoop manual is not clear. I will write in more details:
"Since Sqoop breaks down export process into multiple transactions, it is possible that a failed export job may result in partial data being committed to the database. This can further lead to subsequent jobs failing due to insert collisions in some cases, or lead to duplicated data in others. You can overcome this problem by specifying a staging table via the --staging-table option which acts as an auxiliary table that is used to stage exported data. The staged data is finally moved to the destination table in a single transaction.
In order to use the staging facility, you must create the staging table prior to running the export job. This table must be structurally identical to the target table. This table should either be empty before the export job runs, or the --clear-staging-table option must be specified. If the staging table contains data and the --clear-staging-table option is specified, Sqoop will delete all of the data before starting the export job."
Source: https://sqoop.apache.org/do...
Upvote ShareHow is the merge-key parameter different than --last-modified parameter? Which of the two updates the rows in the table in HDFS?
Upvote ShareCan somebody help me here please?
Upvote ShareHi Sapna,
Please go thru this.
Table 25. Merge options:
ArgumentDescription
--class-name <class>Specify the name of the record-specific class to use during the merge job.
--jar-file <file>Specify the name of the jar to load the record class from.
--merge-key <col>Specify the name of a column to use as the merge key.
--new-data <path>Specify the path of the newer dataset.
--onto <path>Specify the path of the older dataset.
--target-dir <path>Specify the target path for the output of the merge job.
The merge tool runs a MapReduce job that takes two directories as input: a newer dataset, and an older one. These are specified with --new-data and --onto respectively. The output of the MapReduce job will be placed in the directory in HDFS specified by --target-dir.
When merging the datasets, it is assumed that there is a unique primary key value in each record. The column for the primary key is specified with --merge-key. Multiple rows in the same dataset should not have the same primary key, or else data loss may occur.
To parse the dataset and extract the key column, the auto-generated class from a previous import must be used. You should specify the class name and jar file with --class-name and --jar-file. If this is not availab,e you can recreate the class using the codegen tool.
The merge tool is typically run after an incremental import with the date-last-modified mode (sqoop import --incremental lastmodified …).
Supposing two incremental imports were performed, where some older data is in an HDFS directory named older and newer data is in an HDFS directory named newer, these could be merged like so:
$ sqoop merge --new-data newer --onto older --target-dir merged \
--jar-file datatypes.jar --class-name Foo --merge-key id
This would run a MapReduce job where the value in the id column of each row is used to join rows; rows in the newer dataset will be used in preference to rows in the older dataset.
This can be used with both SequenceFile-, Avro- and text-based incremental imports. The file types of the newer and older datasets must be the same.
Upvote ShareHow is the eval command different from sqoop list-tables command?
Upvote ShareCan somebody help me here please
Upvote ShareHi Sapna,
The eval command executes whatever sql you provide the database. This can be any sql command.
For example:
$ sqoop eval --connect jdbc:mysql://c.cloudxlab.com/sqo... --username sqoopuser -e “select * from widgets”
It does not do any operation on the hadoop side.
Upvote ShareSqoop Lab : Hi , I am trying to filter the data before importing in HDFS using sqoop CLI, However filteration using --where or Query is not getting considered. I can see entire getting imported. Please correct me in case of any error in command?
Command used :
sqoop import --connect jdbc:mysql://ip-172-31-13-154/retail_db --username sqoopuser -p --table products
--query "select * from products where product_category_id > 50 "
sqoop import --connect jdbc:mysql://ip-172-31-13-154/retail_db --username sqoopuser -p --table departments
Upvote Share--where "department_id > 7"
We somehow missed this comment. We are looking into it.
Upvote ShareHi Saurabh,
Just curious of you found the solution to this?
I'm able to do this with below query
sqoop import --connect jdbc:mysql://ip-172-31-13-154/retail_db --query "select * from products where product_cate gory_id > 50 AND \$CONDITIONS" -m 2 --username sqoopuser -P --split-by product_id --target-dir testing_1
Let me know if this helps.
Upvote Sharewhen will be the remaining videos will be posted, my subscription is coming to an end this month
Upvote Share