Show Databases

Show Databases

Description:
Displays all databases currently registered in the in-memory catalog. The function reads database metadata from the loaded catalog and prints the database names to the console.

Function:

pub fn show_databases(catalog: &Catalog)

Input:

• catalog — Read-only reference to the in-memory catalog containing database metadata.

Output:

• No return value (()).
• Prints the list of database names to the console.
• If no databases exist, prints:

  No databases found.

Implementation:

1. Log a header indicating that database information is being displayed.
2. Check whether catalog.databases is empty.
3. If no databases exist:
   • Log the message.
   • Print "No databases found.".
   • Return immediately.
4. Iterate through all keys in:

   catalog.databases

5. Print each database name to the console.
6. Log the displayed database names.

Internal API Calls:

• catalog.databases.is_empty()

  • Checks whether any databases are registered in the catalog.

• catalog.databases.keys()

  • Retrieves all database names stored in the catalog.

• log::debug!(...)

  • Writes debug information to the logging system.

• log::info!(...)

  • Writes informational messages to the logging system.

• println!(...)

  • Displays database names to the user.

Files Created/Modified:

• None.

Catalog Updates:

• None.
• The function is read-only and does not modify catalog metadata.