Function join

Constructs AqlQuery objects from an array of arbitrary values.

Note: Nesting aql template strings is a much safer alternative for most use cases. This low-level helper function only exists to complement the aql tag when constructing complex queries from dynamic arrays of query fragments.

Example

const users = db.collection("users");
const filters = [];
if (adminsOnly) filters.push(aql`FILTER user.admin`);
if (activeOnly) filters.push(aql`FILTER user.active`);
const result = await db.query(aql`
  FOR user IN ${users}
  ${join(filters)}
  RETURN user
`);

Example

const users = db.collection("users");
const keys = ["jreyes", "ghermann"];

// BAD! NEEDLESSLY COMPLEX!
const docs = keys.map(key => aql`DOCUMENT(${users}, ${key}`));
const result = await db.query(aql`
  FOR user IN [
    ${join(docs, ", ")}
  ]
  RETURN user
`);
// Query:
//   FOR user IN [
//     DOCUMENT(@@value0, @value1), DOCUMENT(@@value0, @value2)
//   ]
//   RETURN user
// Bind parameters:
//   @value0 -> "users"
//   value1 -> "jreyes"
//   value2 -> "ghermann"

// GOOD! MUCH SIMPLER!
const result = await db.query(aql`
  FOR key IN ${keys}
  LET user = DOCUMENT(${users}, key)
  RETURN user
`);
// Query:
//   FOR user IN @value0
//   LET user = DOCUMENT(@@value1, key)
//   RETURN user
// Bind parameters:
//   value0 -> ["jreyes", "ghermann"]
//   @value1 -> "users"