Convert SQL queries to ElasticSearch syntax

The application supports a very limited subset of sql. This is a work in progress. Here are some examples of what works.

SELECT with specific column names and a variety of criteria

SELECT name, type, state, pin
FROM cities
WHERE name LIKE 'M%'
   AND state = 'FL'
   AND zipCode IN (33126, 33151)
   AND averageAge BETWEEN 34 AND 65
   AND averageSalary >= 55230
   AND averageTemperature < 80

SELECT all columns with criteria

SELECT *
FROM Planets
WHERE SpacecraftWithinKilometers < 10000

GROUP BY with criteria

SELECT SolarSystem, Galaxy
FROM Planets
WHERE SpacecraftWithinKilometers < 10000
GROUP BY SolarSystem, Galaxy

At the moment the following things do not work:

• Sorting
• Inequality operator (!=)
• Common SQL functions like GetDate, DateDiff, Count(*), etc are not supported yet

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