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h2o (version 3.40.0.4)

h2o.import_sql_select: Import SQL table that is result of SELECT SQL query into H2O

Description

Creates a temporary SQL table from the specified sql_query. Runs multiple SELECT SQL queries on the temporary table concurrently for parallel ingestion, then drops the table. Be sure to start the h2o.jar in the terminal with your downloaded JDBC driver in the classpath: `java -cp <path_to_h2o_jar>:<path_to_jdbc_driver_jar> water.H2OApp` Also see h2o.import_sql_table. Currently supported SQL databases are MySQL, PostgreSQL, MariaDB, Hive, Oracle and Microsoft SQL Server.

Usage

h2o.import_sql_select(
  connection_url,
  select_query,
  username,
  password,
  use_temp_table = NULL,
  temp_table_name = NULL,
  optimize = NULL,
  fetch_mode = NULL
)

Arguments

connection_url

URL of the SQL database connection as specified by the Java Database Connectivity (JDBC) Driver. For example, "jdbc:mysql://localhost:3306/menagerie?&useSSL=false"

select_query

SQL query starting with `SELECT` that returns rows from one or more database tables.

username

Username for SQL server

password

Password for SQL server

use_temp_table

Whether a temporary table should be created from select_query

temp_table_name

Name of temporary table to be created from select_query

optimize

(Optional) Optimize import of SQL table for faster imports. Experimental. Default is true.

fetch_mode

(Optional) Set to DISTRIBUTED to enable distributed import. Set to SINGLE to force a sequential read from the database Can be used for databases that do not support OFFSET-like clauses in SQL statements.

Details

For example, my_sql_conn_url <- "jdbc:mysql://172.16.2.178:3306/ingestSQL?&useSSL=false" select_query <- "SELECT bikeid from citibike20k" username <- "root" password <- "abc123" my_citibike_data <- h2o.import_sql_select(my_sql_conn_url, select_query, username, password)