database
70 articles on database — what drives the cost, how it is priced, and where the savings actually are.
Managed PostgreSQL cost compared: RDS vs Cloud SQL vs Azure Flexible Server
AWS RDS, GCP Cloud SQL, and Azure Database for PostgreSQL Flexible Server price managed Postgres similarly, compute per vCPU and memory, storage, and high-availability options. The cost drivers and levers are shared. This compares them.
AWS Keyspaces cost: serverless Cassandra billed per request and GB
Keyspaces (managed Cassandra) bills read and write request units, storage per GB-month, and optional features, with on-demand and provisioned capacity modes. It scales to zero with no clusters to manage. Here is how it prices versus self-managed Cassandra.
AWS DynamoDB global tables cost: you replicate writes and storage
Global tables replicate a DynamoDB table across regions, so you pay replicated write capacity, storage in every region, and cross-region replication transfer. The multiplier is the number of regions. Here is when multi-region is worth it.
GCP Cloud SQL editions cost: Enterprise vs Enterprise Plus
Cloud SQL now has two editions: Enterprise and Enterprise Plus. Enterprise Plus costs more per vCPU and memory but adds a data cache, better performance, and near-zero-downtime maintenance. Here is how the editions price and when the upgrade pays off.
GCP AlloyDB cost: compute per vCPU-hour plus regional storage
AlloyDB bills compute per vCPU-hour and memory, plus regional storage per GB-month with no separate I/O charge, plus backups. It is a PostgreSQL-compatible database aimed at demanding workloads. Here is how it prices versus Cloud SQL.
AWS Timestream cost: writes, tiered storage, and queries scanned
Timestream bills writes per million, storage in a fast memory tier (per GB-hour) and a cheap magnetic tier (per GB-month), and queries per GB scanned. Tuning retention between tiers and scanning less are the levers. Here is the model.
Azure Cosmos DB serverless cost: pay per request unit consumed
Cosmos DB serverless bills per request unit (RU) consumed plus storage, with no provisioned throughput to pay for when idle. It suits spiky or low-traffic workloads; steady high traffic is cheaper on provisioned throughput. Here is how to choose.
Read replicas: the cost-versus-performance math
A read replica adds a full instance cost to offload reads and improve read latency, but it does not help writes and adds replication lag. Knowing when a replica pays off, versus caching or a bigger primary, is the decision. Here is the framework.
Connection pooling: cheap capacity you are probably wasting
Every database connection consumes memory on the server, so without pooling you scale the database up just to hold connections. A pooler like PgBouncer or RDS Proxy lets a small database serve many clients. Here is the cost-performance case.
AWS RDS Multi-AZ cost: you pay for the standby you hope never runs
Multi-AZ roughly doubles instance cost by running a standby replica, and mirrors storage, for automatic failover. Multi-AZ cluster deployments add readable standbys. Here is what you pay for high availability and when it is worth it.
GCP Cloud Spanner cost: nodes or processing units, plus storage
Spanner bills compute as nodes (about $0.90/node/hour) or processing units (100 PU = a tenth of a node), plus $0.30 per GB-month of storage, backup, and egress. Processing units let you start small. Here is how to size and control the bill.
GCP Firestore cost: you pay per read, write, and delete
Firestore bills per document operation (reads about $0.06 per 100k, writes about $0.18, deletes about $0.02) plus storage and egress, with a daily free tier. Query patterns, not data size, drive the bill. Here is how to keep operations down.
AWS DocumentDB cost: instance hours, storage, and I/O add up
DocumentDB bills like Aurora: instance hours per node, $0.10 per GB-month of storage, and $0.20 per million I/O requests. On a busy cluster the I/O line often rivals compute. Here is the full breakdown and where to cut.
AWS Neptune cost: provisioned instances vs Serverless, plus I/O
Neptune charges per instance hour (or per NCU on Serverless), $0.10 per GB-month of storage, and $0.20 per million I/O. Serverless scales to your load; provisioned is cheaper when load is steady. Here is how to choose and control the bill.
GCP Bigtable cost optimization: the per-node floor that decides it
Bigtable bills nodes (~$474/month each, minimum one) + storage. The node floor makes it expensive below scale. Here's how to tune nodes, SSD vs HDD, and when a cheaper datastore wins.
DynamoDB cost optimization: capacity mode, GSIs, TTL, and table class
DynamoDB cost is throughput + storage + GSIs + extras. Here's how to cut it: match capacity mode to traffic, prune unused indexes, set TTL, and use Standard-IA for cold tables.
Azure PostgreSQL Flexible Server cost: tiers, HA, and reservations
Flexible Server bills compute by tier (Burstable ~$12/mo, General Purpose, Memory Optimized) + storage. HA doubles compute. Here's how to pick the tier, when to skip HA, and how reservations and stop/start cut the bill.
Azure SQL Database cost: DTU vs vCore and why vCore unlocks the discounts
DTU bundles compute/storage/IO simply; vCore separates them and unlocks Azure Hybrid Benefit and reserved capacity. Here's which is cheaper for your database and when to switch.
Cloud SQL vs AlloyDB cost: when the faster database is also cheaper
AlloyDB costs more per vCPU than Cloud SQL but is much faster for analytical workloads, so it can need less compute for the same performance. Here's how each bills and which to pick.
Azure Cosmos DB RU cost optimization: stop over-provisioning throughput
Cosmos DB bills by provisioned RU/s (~$0.008 per 100 RU/s-hour) times region count. Over-provisioned throughput and needless multi-region writes are the big overspends. Here's how to right-size and which throughput model to pick.
Azure SQL Managed Instance cost: the $1,460/month floor and how to lower it
SQL Managed Instance has a 4-vCore minimum, so even an idle instance starts around $1,460/month on General Purpose. Here's the full pricing breakdown, the Business Critical premium, and the four levers that actually cut the bill.
RDS vs Aurora: cost decision framework
RDS is cheaper per instance hour; Aurora has more efficient storage and built-in replicas. Here's when each one wins, including Aurora I/O Optimized, Aurora Serverless v2, and Reserved Capacity options.