Table structure

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The table in your Tenant is constructed using a single-table design pattern, where the items or rows in the table may be super-wide but very sparse.

Specifically, the table defines the following fields. Additional fields that you store per item are entirely up to you.

Fields

Field	Type	Description	Required
`pk`	String	The partition or hash key for the table	Y
`sk`	String	The sort or range key for the table	Y
`lsi0_sk`	String	The sort or range key for the index `lsi0`	N
`lsi1_sk`	String	The sort or range key for the index `lsi1`	N
`lsi2_sk`	String	The sort or range key for the index `lsi2`	N
`lsi3_sk`	String	The sort or range key for the index `lsi3`	N
`lsi4_sk`	String	The sort or range key for the index `lsi4`	N
`ttl`	Number	The Time-To-Live for the item, in Unix epoch time formate	N

It is strongly recommended that you do not assign any meaning to the pk or various sk fields, and that each of these fields is effectively a copy of a meaningful field that you add to the item.
While the ttl is optional, EchoStream strongly recommends that you use it. It allows your table to automatically clean up old items. You will pay for all items in the table, even those you have lost reference to, and automatic cleanup mitigates this.

Index	Keys	Use
table	`pk` plus `sk`	The primary table index. Supports discrete `GetItem` calls as well as `Query` calls
`lsi0`	`pk` plus `lsi0_sk`	A Local Secondary Index. Supports `Query` calls using the secondary sort key
`lsi1`	`pk` plus `lsi1_sk`	A Local Secondary Index. Supports `Query` calls using the secondary sort key
`lsi2`	`pk` plus `lsi2_sk`	A Local Secondary Index. Supports `Query` calls using the secondary sort key
`lsi3`	`pk` plus `lsi3_sk`	A Local Secondary Index. Supports `Query` calls using the secondary sort key
`lsi4`	`pk` plus `lsi4_sk`	A Local Secondary Index. Supports `Query` calls using the secondary sort key

The pk and sk, in combination, must be unique. If your pk is unique and you do not need the sk, put in a placeholder value for the sk.
Items in your table may provide any number of the lsiX_sk fields for the corresponding indexes, including providing none of them (and just using the table index).
You may have as many items that declare duplicate lsiX_sk fields as you wish. If you do this, your Query calls on the lsiX indexes will return multiple items.
It is strongly recommended that you use the indexes provided where possible. While Scan calls are allowed, they are expensive and slow.

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