# Storing Patient Data using Expressions

Storing Patient Data using Expressions

When implementing postcoordinated SNOMED CT expressions, there are different approaches to storage that may be considered.

* [Store the full expression in the same way as you would store any coded data item](https://docs.snomed.org/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-the-full-expression)
* [Reference the expression in the record storage using a local expression identifier, and hold the expressions in a separate expression repository](https://docs.snomed.org/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-expression-identifier)
* [Store the expression parts individually in separate fields](https://docs.snomed.org/snomed-ct-practical-guides/snomed-ct-postcoordination-guide/expressions-in-the-ehr/storing-patient-data-using-expressions/store-expression-parts-individually)

These approaches are described in the following pages.

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