JSONB field name incorrectly handled by `sql()`

[JakobJingleheimer]

Take a simple query like

sql`
SELECT * FROM "Example"
  WHERE
    somejsonb->>'someField' = foo;
`

When built dynamically:

// fieldName → somejsonb->>'someField'
// val → 'foo'

sql`
SELECT * FROM "Example"
  WHERE
    ${sql(fieldName)} = ${val};
`

fieldName is incorrectly quoted as "somejsonb->>'someField'" (it should be "somejsonb"->>'someField')

Manually wrapping somejsonb in double-quotes results in an extra set of quotes: ""somejsonb"->>'someField'"

[emogua]

I think sql(fieldName) should be recognized as 'column name', so ${sql(fieldName)} will outputed as "fieldName", wrapped using double quotes
I think there are two solutions:
1: somejsonb->>${'someField'} = ${val}
2: just using unsafe but you should care about sql injection: ${sql.unsafe(fieldName)} = ${val}

[JakobJingleheimer]

I think sql() should handle this (otherwise it's quite a foot-gun IMO), but there is a workaround.

There was a bigger foot-gun lurking though: the lack of join (#905).

I've sent an update to the README with these caveats and workarounds.