imported>OCDoc Import: Imported from legacy OpenComputers documentation at ocdoc.cil.li

2026-08-24T08:08:27Z

Imported from legacy OpenComputers documentation at ocdoc.cil.li

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= Component: Database =

This component is provided by the [[Item/database upgrade|database upgrade]].

Component name: `database`.

The database component is primarily useful to work with "full" item stacks, including NBT tags, which are (by default) not available to Lua scripts (to avoid exploits / breaking of other mods' gameplay). Some components allow specifying item stacks by instead specifying the address of a database component, and slot the item stack is in that database - for example, the Export Bus driver for Applied Energistics 2 makes use of this functionality.

Callbacks:

* `get(slot:number):table`

<pre>Get the representation of the item stack stored in the specified slot.
</pre>
* `computeHash(slot:number):string`

<pre>Computes a hash value for the item stack in the specified slot. This value is guaranteed to be the same for identical item stacks, allowing comparison of item stacks across a network (by comparing the hash values).
</pre>
* `indexOf(hash:string):number`

<pre>Get the index of an item stack with the specified hash. Returns a negative value if no such stack was found.
</pre>
* `clear(slot:number):boolean`

<pre>Clears the specified slot. Returns true if there was something in the slot before.
</pre>
* `copy(fromSlot:number, toSlot:number[, address:string]):boolean`

<pre>Copies an entry to another slot, optionally to another database. Returns true if something was overwritten.
</pre>
* `clone(address:string):number`

<pre>Copies the data stored in this database to another database with the specified address.
</pre>
Example Use:

```lua local component = require("component") local sides = require("sides")

local db = component.database -- primary database component local invcontrol = component.inventory_controller -- primary inventory controller

-- define slot numbers dbSlot = 1 invSlot = 1

-- compare item inside remote inventory to item in first slot of database if db.get(dbSlot).label == invcontrol.getStackInSlot(sides.north, invSlot).label then

<pre> -- items match, do stuff with it.
</pre>
else

<pre> -- items don't match, do nothing, or do something else.
</pre>
== end ``` ==

{{:Component/contents}}

Component/database - Revision history

imported>OCDoc Import: Imported from legacy OpenComputers documentation at ocdoc.cil.li