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Lens –

Jdbc driver configuration


The configuration parameters and their default values
No. Property Name Default Value Description
1 lens.cube.query.driver.supported.storages List of comma separated storage names that supported by a driver. If no value is specified, all storages are valid
2 lens.cube.query.partition.where.clause.format yyyy-MM-dd HH:mm:ss The simple date format of how the queried partition should be put in where clause. If nothing is specified, it will use the format from org.apache.lens.cube.metadata.UpdatePeriod for each type of partition
3 lens.cube.query.replace.timedim false Tells whether timedim attribute queried in the time range should be replaced with its corresponding partition column name.
4 lens.cube.query.time.range.writer.class org.apache.lens.cube.parse.BetweenTimeRangeWriter The timerange writer class which specifies how the resolved partitions in timeranges should be written in final query. Available writers are org.apache.lens.cube.parse.ORTimeRangeWriter and org.apache.lens.cube.parse.BetweenTimeRangeWriter
5 lens.driver.jdbc.connection.provider A contract for obtaining JDBC connections
6 lens.driver.jdbc.db.password The database user's password
7 lens.driver.jdbc.db.uri JDBC connection URL in the format jdbc:dbms://host:port/dbname
8 lens.driver.jdbc.db.user The database user on whose behalf the connection is being made
9 lens.driver.jdbc.driver.class com.mysql.jdbc.Driver Type of JDBC driver used to connect backend database
10 lens.driver.jdbc.enable.resultset.streaming.retrieval false Flag to enable row by row retrieval of result set from the database server. This is used to enable streaming result sets for MySQL. This is set to false by default.
11 lens.driver.jdbc.estimate.db.password The database user's password, for estimate queries. If this property is unspecified, value for lens.driver.jdbc.db.password would be used. Override this property to tune estimate connection pool
12 lens.driver.jdbc.estimate.db.uri JDBC connection URL in the format jdbc:dbms://host:port/dbname for estimate queries. If this property is unspecified, value for lens.driver.jdbc.db.uri will be used.
13 lens.driver.jdbc.estimate.db.user The database user on whose behalf the connection is being made, for estimate queries. If this property is unspecified, value for lens.driver.jdbc.db.user would be used. Override this property to tune estimate connection pool
14 lens.driver.jdbc.estimate.driver.class Type of JDBC driver used to connect backend database for estimate queries. If This property is not specified, value for lens.driver.jdbc.driver.class will be used. Override this property to tune estimate connection pool
15 lens.driver.jdbc.estimate.get.connection.timeout Response timeout in milliseconds of any JDBC call invoking data transmission over a connection socket , for estimate queries. If this property is not specified, value for lens.driver.jdbc.get.connection.timeout would be used. Override this property to tune estimate connection pool.
16 lens.driver.jdbc.estimate.pool.idle.time Maximum idle time in sec before a connection is closed, for estimate queries. If this property is not specified, value for lens.driver.jdbc.pool.idle.time would be used. Override this property to tune estimate connection pool.
17 lens.driver.jdbc.estimate.pool.max.size Maximum number of concurrent connections allowed in pool, for estimate queries. If this property is unspecified, value for lens.driver.jdbc.pool.max.size would be used. Override this property to tune estimate connection pool
18 lens.driver.jdbc.estimate.pool.max.statements Maximum number of prepared statements to cache per connection, for estimate queries. If this property is not specified, value for lens.driver.jdbc.pool.max.statements would be used.
19 lens.driver.jdbc.explain.keyword Explain Explain keyword used to get the query plan of underlying database
20 lens.driver.jdbc.fetch.size 1000 Fetch size for JDBC result set
21 lens.driver.jdbc.get.connection.timeout 10000 Response timeout in milliseconds of any JDBC call invoking data transmission over a connection socket
22 lens.driver.jdbc.pool.idle.time 600 Maximum idle time in sec before a connection is closed
23 lens.driver.jdbc.pool.max.size 15 Maximum number of concurrent connections allowed in pool
24 lens.driver.jdbc.pool.max.statements 20 Maximum number of prepared statements to cache per connection
25 lens.driver.jdbc.query.rewriter org.apache.lens.driver.jdbc.ColumnarSQLRewriter Rewriting the HQL to optimized sql queries
26 lens.driver.jdbc.validate.through.prepare true Flag to enable query syntactic and semantic validation using prepared statement.