HogQL Autocomplete

[Gilbert09]

HogQL Autocomplete TODOs

What's the goal of this?

To add autocomplete/intellisense support to writing HogQL queries in PostHog. Allowing users to be able to identify and select fields, properties, and general SQL keywords

Step 1: Make it work

• Fields on tables
  • Lazy join fields
  • Recursive fields
  • Field traversers
• Table aliases
• Properties (StringJSONDatabaseField type)
  • Property types (string/int/etc)
• Table names
• Common table expressions
  • Returning a subset of fields from a table
  • Constant types (returning a "string" and not a db column)

Step 2: Make it good

• Support ast.SelectUnionQuery
• Support field aliases in where/order by/group by clauses
• Join aliases and join constraints
• Documentation for functions (requires type system update)
  • Parameter support
• Suggest SQL keywords
• Field hover support (hover over field names for extra info)
• Support HogQL expressions, such as within trends
• Awareness of Cohorts
  • Suggest cohort names
• Autocomplete value suggestions, e.g. return Chrome/Safari/etc when comparing properties.$browser in a where clause
  • Also show these in the field "documentation" field
• Automagically suggest wrapping values in a to<Type> function when there's a type mismatch in comparisons

Step 3: Make it complete

• ???

Others

• Report on performance
• Insights on usage