extend the parsing method to support philipps crazy sql

[mpbismar]

• [ ] support substring-function

[philipp94831]

Preferred:

SELECT patient_num, concept_cd, count(*) AS count
FROM (
    SELECT patient_num, substring(concept_cd from '.*:.{3}') AS concept_cd
    FROM i2b2demodata.observation_fact
    WHERE concept_cd IN (
        SELECT concept_cd
        FROM i2b2demodata.concept_dimension
        WHERE concept_cd SIMILAR TO '(ATC|ICD):%')
    AND (start_date >= '2007-01-01T00:00:00' AND start_date <= '2008-01-01T00:00:00')
    AND (FALSE
    OR patient_num IN (
        SELECT patient_num
        FROM i2b2demodata.qt_patient_set_collection
        WHERE result_instance_id = 7)
    )) observations
GROUP BY patient_num, concept_cd

Compromise:

SELECT patient_num, concept_cd, count(*) AS count
FROM (
    SELECT patient_num, substring(concept_cd from 1 for 7) AS concept_cd
    FROM i2b2demodata.observation_fact
    WHERE concept_cd IN (
        SELECT concept_cd
        FROM i2b2demodata.concept_dimension
        WHERE (concept_cd LIKE 'ATC:%'
        OR concept_cd LIKE 'ICD:%'))
    AND (start_date >= '2007-01-01T00:00:00' AND start_date <= '2008-01-01T00:00:00')
    AND (FALSE
    OR patient_num IN (
        SELECT patient_num
        FROM i2b2demodata.qt_patient_set_collection
        WHERE result_instance_id = 7)
    )) observations
GROUP BY patient_num, concept_cd