Common-Data-Model / Impala ================= This folder contains the SQL scripts for Impala. In order to create your instantiation of the Common Data Model, we recommend following these steps: 1. Create an empty schema. ```bash impala-shell -q 'CREATE DATABASE omop_cdm' ``` 2. Execute the script `OMOP CDM impala ddl.txt` (you will need to convert it to a sql file first) to create the tables and fields. ```bash impala-shell -d omop_cdm -f OMOP_CDM_impala_ddl.sql ``` 3. Load your data into the schema. a. Load the vocabulary tables. First, download the data from [http://www.ohdsi.org/web/athena/](http://www.ohdsi.org/web/athena/) and unzip into a _cdmv5vocab_ directory, then run ```bash hadoop fs -put cdmv5vocab cdmv5vocab hadoop fs -chmod +w cdmv5vocab impala-shell -d omop_cdm -f VocabImport/OMOP_CDM_vocabulary_load_Impala.sql --var=OMOP_VOCAB_PATH=/user/$USER/cdmv5vocab ``` b. Load the patient data. For example, download the 1000 person sample of simulated CMS SynPUF patient data from [http://www.ltscomputingllc.com/downloads/](http://www.ltscomputingllc.com/downloads/) and unzip into a _synpuf_ directory, then run ```bash hadoop fs -put synpuf synpuf hadoop fs -chmod +w synpuf impala-shell -d omop_cdm -f DataImport/OMOP_CDM_synpuf_load_Impala.sql --var=OMOP_SYNPUF_PATH=/user/$USER/synpuf ``` 4. Convert to Parquet format. ```bash impala-shell -q 'CREATE DATABASE omop_cdm_parquet' impala-shell -f OMOP_Parquet.sql ``` 5. Run simple queries to sanity check. ```bash impala-shell -d omop_cdm_parquet -q 'SELECT COUNT(1) FROM concept' impala-shell -d omop_cdm_parquet -q 'SELECT COUNT(1) FROM person' ```