[
https://issues.apache.org/jira/browse/SPARK-21519?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
]
Luca Canali updated SPARK-21519:
--------------------------------
Description:
This proposes an option to the JDBC datasource, tentatively called "
sessionInitStatement" to implement the functionality of session initialization
present for example in the Sqoop connector for Oracle (see
https://sqoop.apache.org/docs/1.4.6/SqoopUserGuide.html#_oraoop_oracle_session_initialization_statements
) . After each database session is opened to the remote DB, and before
starting to read data, this option executes a custom SQL statement (or a PL/SQL
block in the case of Oracle).
Example of usage, relevant to Oracle JDBC:
val preambleSQL="""
begin
execute immediate 'alter session set tracefile_identifier=sparkora';
execute immediate 'alter session set "_serial_direct_read"=true';
execute immediate 'alter session set time_zone=''+02:00''';
end;
"""
bin/spark-shell –jars ojdb6.jar
val df = spark.read.format("jdbc").option("url",
"jdbc:oracle:thin:@ORACLEDBSERVER:1521/service_name").option("driver",
"oracle.jdbc.driver.OracleDriver").option("dbtable", "(select 1, sysdate,
systimestamp, current_timestamp, localtimestamp from dual)").option("user",
"MYUSER").option("password",
"MYPASSWORK").option("fetchsize",1000).option("sessionInitStatement",
preambleSQL).load()
df.show(5,false)
Comments: This proposal has been developed and tested for connecting the Spark
JDBC data source to Oracle databases, however it believe it can be useful for
other target DBs too, as it is quite generic.
Note the proposed code allows to inject SQL into the target database. This is
not a security concern as such, as it requires password authentication, however
beware of the possibilities for injecting user-provided SQL (and PL/SQL) that
this opens.
was:
This proposes an option to the JDBC datasource, tentatively called "
sessionInitStatement" to implement the functionality of session initialization
present for example in the Sqoop connector for Oracle (see
https://sqoop.apache.org/docs/1.4.6/SqoopUserGuide.html#_oraoop_oracle_session_initialization_statements
) . After each database session is opened to the remote DB, and before
starting to read data, this option executes a custom SQL statement (or a PL/SQL
block in the case of Oracle).
Example of usage, relevant to Oracle JDBC:
```
val preambleSQL="""
begin
execute immediate 'alter session set tracefile_identifier=sparkora';
execute immediate 'alter session set "_serial_direct_read"=true';
execute immediate 'alter session set time_zone=''+02:00''';
end;
bin/spark-shell –jars ojdb6.jar
val df = spark.read.format("jdbc").option("url",
"jdbc:oracle:thin:@ORACLEDBSERVER:1521/service_name").option("driver",
"oracle.jdbc.driver.OracleDriver").option("dbtable", "(select 1, sysdate,
systimestamp, current_timestamp, localtimestamp from dual)").option("user",
"MYUSER").option("password",
"MYPASSWORK").option("fetchsize",1000).option("sessionInitStatement",
preambleSQL).load()
df.show(5,false)
```
Comments: This proposal has been developed and tested for connecting the Spark
JDBC data source to Oracle databases, however it believe it can be useful for
other target DBs too, as it is quite generic.
Note the proposed code allows to inject SQL into the target database. This is
not a security concern as such, as it requires password authentication, however
beware of the possibilities for injecting user-provided SQL (and PL/SQL) that
this opens.
> Add an option to the JDBC data source to initialize the environment of the
> remote database session
> --------------------------------------------------------------------------------------------------
>
> Key: SPARK-21519
> URL: https://issues.apache.org/jira/browse/SPARK-21519
> Project: Spark
> Issue Type: New Feature
> Components: SQL
> Affects Versions: 2.1.0, 2.1.1, 2.2.0
> Reporter: Luca Canali
> Priority: Minor
>
> This proposes an option to the JDBC datasource, tentatively called "
> sessionInitStatement" to implement the functionality of session
> initialization present for example in the Sqoop connector for Oracle (see
> https://sqoop.apache.org/docs/1.4.6/SqoopUserGuide.html#_oraoop_oracle_session_initialization_statements
> ) . After each database session is opened to the remote DB, and before
> starting to read data, this option executes a custom SQL statement (or a
> PL/SQL block in the case of Oracle).
> Example of usage, relevant to Oracle JDBC:
> val preambleSQL="""
> begin
> execute immediate 'alter session set tracefile_identifier=sparkora';
> execute immediate 'alter session set "_serial_direct_read"=true';
> execute immediate 'alter session set time_zone=''+02:00''';
> end;
> """
> bin/spark-shell –jars ojdb6.jar
> val df = spark.read.format("jdbc").option("url",
> "jdbc:oracle:thin:@ORACLEDBSERVER:1521/service_name").option("driver",
> "oracle.jdbc.driver.OracleDriver").option("dbtable", "(select 1, sysdate,
> systimestamp, current_timestamp, localtimestamp from dual)").option("user",
> "MYUSER").option("password",
> "MYPASSWORK").option("fetchsize",1000).option("sessionInitStatement",
> preambleSQL).load()
> df.show(5,false)
> Comments: This proposal has been developed and tested for connecting the
> Spark JDBC data source to Oracle databases, however it believe it can be
> useful for other target DBs too, as it is quite generic.
> Note the proposed code allows to inject SQL into the target database. This is
> not a security concern as such, as it requires password authentication,
> however beware of the possibilities for injecting user-provided SQL (and
> PL/SQL) that this opens.
--
This message was sent by Atlassian JIRA
(v6.4.14#64029)
---------------------------------------------------------------------
To unsubscribe, e-mail: issues-unsubscr...@spark.apache.org
For additional commands, e-mail: issues-h...@spark.apache.org
