[IGNITE-17179] Thin 3.0: SQL metadata caching

• Type: Improvement
• Status: Open
• Priority: Minor
• Resolution: Unresolved
• Affects Version/s: 3.0.0-alpha5
• Fix Version/s: 3.1
• Component/s: thin client
• Labels: ignite-3
• Ignite Flags: Docs Required, Release Notes Required
• Assignee: Pavel Tupitsyn
• Reporter: Pavel Tupitsyn
• Created: 15/Jun/22 17:56
• Updated: 04/Sep/24 16:29

Description

We send query metadata to the client with every request (IGNITE-17052). It is a waste of resources when the same query is executed frequently.

• Cache metadata on server, generate unique ID
• Return the ID to the client
• Client retrieves cached metadata from server when not known, caches it locally

However, some queries can be one-off and unique. The cache can grow too big over the lifetime of the application.

• Use the cache only for queries that have executed N times (detect this on the server)
• Limit cache size, use LRU eviction (client and server)

Do not use query text as cache key - column types can change. Use the entire metadata content to check cache entry equality.

Issue Links

• is related to: IGNITE-17052 Thin 3.0: Implement query metadata