Creating two dynamoDB tables in serverless.yml - node.js

Question

I'm try to add 2 tables to serverless.yml to link with DynamoDB.
A part of my code in serverless.yml:
...
resources:
Resources:
ItemsTable:
Type: "AWS::DynamoDB::Table"
Properties:
TableName: "InvoiceConfig"
AttributeDefinitions:
- AttributeName: "providerName"
AttributeType: "S"
KeySchema:
- AttributeName: "providerName"
KeyType: "HASH"
ProvisionedThroughput:
ReadCapacityUnits: 2
WriteCapacityUnits: 2
TableName: "DifferentTermsPages"
AttributeDefinitions:
- AttributeName: "id"
AttributeType: "S"
- AttributeName: "providerName"
AttributeType: "S"
- AttributeName: "productType"
AttributeType: "S"
- AttributeName: "language"
AttributeType: "S"
- AttributeName: "terms"
AttributeType: "L"
KeySchema:
- AttributeName: "id"
KeyType: "HASH"
- AttributeName: "providerName"
KeyType: "HASH"
- AttributeName: "productType"
KeyType: "HASH"
- AttributeName: "language"
KeyType: "HASH"
- AttributeName: "terms"
KeyType: "HASH"
ProvisionedThroughput:
ReadCapacityUnits: 10
WriteCapacityUnits: 10
Is that correct??
My tables are:
InvoiceConfig: with columns: providerName (String)
DifferentTermsPages: id (String), providerName (String), productType (String), language (String), terms (list)
Do I need more changes in serverles.yml? what is the meaning of the expressions "ReadCapacityUnits" and "WriteCapacityUnits"?

Answer 1

There should be some separation between two resources (i.e. two DynamoDB tables).
Note:-
You can define only key attributes while creating the DynamoDB table. In other words, you don't need to define all other non-key attributes.
Try this:-
Resources:
ItemsTable:
Type: "AWS::DynamoDB::Table"
Properties:
TableName: "InvoiceConfig"
AttributeDefinitions:
- AttributeName: "providerName"
AttributeType: "S"
KeySchema:
- AttributeName: "providerName"
KeyType: "HASH"
ProvisionedThroughput:
ReadCapacityUnits: 2
WriteCapacityUnits: 2
DifferentTermsPages:
Type: "AWS::DynamoDB::Table"
Properties:
TableName: "DifferentTermsPages"
AttributeDefinitions:
- AttributeName: "id"
AttributeType: "S"
KeySchema:
- AttributeName: "id"
KeyType: "HASH"
ProvisionedThroughput:
ReadCapacityUnits: 10
WriteCapacityUnits: 10
Read and Write capacity units:-
You specify throughput capacity in terms of read capacity units and
write capacity units:
One read capacity unit represents one strongly consistent read per
second, or two eventually consistent reads per second, for an item up
to 4 KB in size. If you need to read an item that is larger than 4 KB,
DynamoDB will need to consume additional read capacity units. The
total number of read capacity units required depends on the item size,
and whether you want an eventually consistent or strongly consistent
read. One write capacity unit represents one write per second for an
item up to 1 KB in size. If you need to write an item that is larger
than 1 KB, DynamoDB will need to consume additional write capacity
units. The total number of write capacity units required depends on
the item size.
Read and write capacity units

Answer 2

Short Answer:
Read and Write Capacity Units are the max size of data the db is allowed to processes per second, if you go over this amount in any second your request would throttle.
Alternative:
It might be easier to just use DynamoDB On-Demand and pay for the Db table usages rather than calculating WCU and RCU.
Example
Here is an example of 3 tables added in a formatted manner and without semiquotes:
resources:
Resources:
myDynamoDBTable1:
Type: AWS::DynamoDB::Table
Properties:
TableName: Table1
AttributeDefinitions:
- AttributeName: ColumnName1
AttributeType: S
- AttributeName: ColumnName2
AttributeType: N
KeySchema:
- AttributeName: ColumnName1
KeyType: HASH
- AttributeName: ColumnName2
KeyType: RANGE
ProvisionedThroughput:
ReadCapacityUnits: 1
WriteCapacityUnits: 1
myDynamoDBTable2:
Type: AWS::DynamoDB::Table
Properties:
TableName: Table2
AttributeDefinitions:
- AttributeName: ColumnName1
AttributeType: S
KeySchema:
- AttributeName: ColumnName1
KeyType: HASH
BillingMode: PAY_PER_REQUEST
myDynamoDBTableN:
Type: AWS::DynamoDB::Table
Properties:
TableName: TableN
AttributeDefinitions:
- AttributeName: ColumnName1
AttributeType: S
KeySchema:
- AttributeName: ColumnName1
KeyType: HASH
BillingMode: PAY_PER_REQUEST
Additional Explanation with Examples:
Back to Read/Write Capacity Mode:
Write Capacity Units (WCU) formula: Round up (DataSize / 1KB)
Example1:
imagine you foresee a traffic of writing 10KB of data per second into the db. Using the WCU formula, you would need (10KB / 1KB) = 10WCU.
Example2:
Expecting writing traffic of 7.5KB of data to the db, we would need: (7.5KB / 1KB) = 8WCU
Reading Capacity Units (RCU) depends on Strongly or Eventually Consistent models.
Strongly Consistent mode: Round up (DataSize / 4KB)
Eventually Consistent mode: Round up(DataSize / 4KB) / 2