Connecting to the Database and Inspecting Its Structure In this step, you will set up your environment, connect to the database, and inspect its contents. Follow the instructions below to begin: Open RStudio: Go to File New File Script to create a new script. Clean the Environment and Load Required Libraries: Copy and run the following code in your script to clean your environment and load the necessary libraries: rm(list = ls()) library(DBI) library(RSQLite) library(sqldf) library(RMariaDB) Connect to the Database: Use the following function to establish a connection to the database: connect_database

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Connecting to the Database and Inspecting Its Structure In this step, you will set up your environment, connect to the database, and inspect its contents. Follow the instructions below to begin: Open RStudio: Go to File > New File > Script to create a new script. Clean the Environment and Load Required Libraries: Copy and run the following code in your script to clean your environment and load the necessary libraries: rm(list = ls()) library(DBI) library(RSQLite) library(sqldf) library(RMariaDB) Connect to the Database: Use the following function to establish a connection to the database: connect_database <- function(user, password, dbname, host, bigint = "integer") { con <- dbConnect(drv = RMariaDB::MariaDB(), user = user, password = password, dbname = dbname, host = host, bigint = bigint) print("Connected to database. Available tables:") print(dbListTables(con)) invisible(con) } db <- connect_database(user='student',password='cbasummer2020',dbname='stedmans',host='dadata.bensresearch.com') This function is designed to: Specify the database type, user credentials, and host address. Establish a connection to the database. List all available tables within the database. Inspect the Database: After running the code, look at the output in your RStudio console. The function will display a list of tables available in the database. Task: Answer the following question: How many tables do you see in this database?

BlackTom AI · Accepted Answer

The question asks: How many tables do you see in this database?

To reason about this, focus on what the supplied R function and subsequent code actually output. The connect_database function establishes a connection to the MariaDB database and then prints the list of tables using dbListTables(con). The task then tells you to inspect the database by looking at the console output after running the code.

Key steps and what they produce:
- The function dbConnect(...) attempts to open a connection to the specified host with the given credentials. If the connection fails, the subsequent print of tables will not occur, and you would need to troubleshoot the connection first.
- If the connection succeeds, the line print(dbListTables(con)) executes. This prints a character vector of table names that exist in the database. The number of tables is simply the length of that vector.

Given that the database content is not shown here, we cannot deterministically state the number of tables from the information provided. The actual count depends entirely on the database state at runtime.

To determine the number of tables yourself, you would:
- Run the code as provided with the correct credentials and host. 
- Observe the console output where the message "Connected to database. Available tables:" is followed by a list of table names.
- Count how many entries appear in that printed list, or alternatively compute length(dbListTables(con)) if you run additional code like: tbls <- dbListTables(con); length(tbls).

Common points of confusion to watch for:
- If the connection fails, you will not see any table names printed, so the count cannot be determined from the output—troubleshooting the connection parameters would be needed.
- If the database has views or temporary tables, they may or may not appear in dbListTables depending on the database and client configuration.
- The parameter bigint = "integer" in the connection call does not affect the table count; it only influences how big integer types are handled, so it does not change the number of tables.

In summary, the exact number of tables is not specified in the provided text and must be read off from the console output after executing the code. If you run it and capture the list, you can count its entries to obtain the answer.

ECON3310001.1251 Lab Nine

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