generic

package generic

Type Members

trait GenericAEVT extends AnyRef
AEVT Index.
AEVT Index.
"The AEVT index provides efficient access to all values for a given attribute, comparable to traditional column access style." (from Datomic documentation)
Access the AEVT Index in Molecule by instantiating an AEVT object with one or more arguments and then add generic attributes:
```
for {
  // Create AEVT Index molecule with 1 entity id argument
  _ <- AEVT(":Person/name").e.v.t.get.map(_ ==> List(
    (e1, "Ben", t2),
    (e2, "Liz", t5)
  ))

  // Narrow search with multiple arguments
  _ <- AEVT(":Person/name", e1).e.v.get.map(_ ==> List( (e1, "Ben") ))
  _ <- AEVT(":Person/name", e1, "Ben").e.v.get.map(_ ==> List( (e1, "Ben") ))
  _ <- AEVT(":Person/name", e1, "Ben", t2).e.v.get.map(_ ==> List( (e1, "Ben") ))
} yield ()
```
Index attributes available:
- e - Entity id (Long)
- a - Full attribute name like ":Person/name" (String)
- v - Value of Datoms (Any)
- t - Transaction pointer (Long/Int)
- tx - Transaction entity id (Long)
- txInstant - Transaction wall clock time (java.util.Date)
- op - Operation status: assertion (true) / retraction (false)
Note
The Molecule Index API's don't allow returning the whole Index/the whole database. So omitting arguments constructing the Index object (like AEVT.a.e.v.t.get) will throw an exception.
Please use Datomics API if you need to return the whole database Index:
conn.db.datoms(datomic.Database.AEVT)

trait GenericAVET extends AnyRef

AVET Index.

"The AVET index provides efficient access to particular combinations of attribute and value." (from Datomic documentation)

Access the AVET Index in Molecule by instantiating an AVET object with one or more arguments and then add generic attributes:

for {
  // Create AVET Index molecule with 1 entity id argument
  _ <- AVET(":Person/age").e.v.t.get.map(_ ==> List(
    (e1, 42, t2),
    (e2, 37, t5)
    (e3, 14, t7),
  ))

  // Narrow search with multiple arguments
  _ <- AVET(":Person/age", 42).e.t.get.map(_ ==> List( (e1, t2) ))
  _ <- AVET(":Person/age", 42, e1).e.v.get.map(_ ==> List( (e1, t2) ))
  _ <- AVET(":Person/age", 42, e1, t2).e.v.get.map(_ ==> List( (e1, t2) ))
} yield ()

The AVET Index can be filtered by a range of values between from (inclusive) and until (exclusive) for an attribute:

for {
  _ <- AVET.range(":Person/age", Some(14), Some(37)).v.e.t.get.map(_ ==> List(
    (14, e4, t7) // 14 is included in value range
                 // 37 not included in value range
                 // 42 outside value range
  ))

  // If `from` is None, the range starts from the beginning
  _ <- AVET.range(":Person/age", None, Some(40)).v.e.t.get.map(_ ==> List(
    (14, e3, t7),
    (37, e2, t5),
  ))

  // If `until` is None, the range goes to the end
  _ <- AVET.range(":Person/age", Some(20), None).v.e.t.get.map(_ ==> List(
    (37, e2, t5),
    (42, e1, t2)
  ))
} yield ()

Index attributes available:

e - Entity id (Long)
a - Full attribute name like ":Person/name" (String)
v - Value of Datoms (Any)
t - Transaction pointer (Long/Int)
tx - Transaction entity id (Long)
txInstant - Transaction wall clock time (java.util.Date)
op - Operation status: assertion (true) / retraction (false)

Note: The Molecule Index API's don't allow returning the whole Index/the whole database. So omitting arguments constructing the Index object (like AVET.a.v.e.t.get) will throw an exception.
Please use Datomics API if you need to return the whole database Index:
conn.db.datoms(datomic.Database.AVET)

from and until cannot both be None since Molecule doesn't allow returning all datoms.

trait GenericEAVT extends AnyRef
EAVT Index.
EAVT Index.
"The EAVT index provides efficient access to everything about a given entity. Conceptually this is very similar to row access style in a SQL database, except that entities can possess arbitrary attributes rather then being limited to a predefined set of columns." (from Datomic documentation)
Access the EAVT Index in Molecule by instantiating an EAVT object with one or more arguments and then add generic attributes:
```
for {
  // Create EAVT Index molecule with 1 entity id argument
  _ <- EAVT(e1).e.a.v.t.get.map(_ ==> List(
    (e1, ":Person/name", "Ben", t1),
    (e1, ":Person/age", 42, t2),
    (e1, ":Golf/score", 5.7, t2)
  ))

  // Narrow search with multiple arguments
  _ <- EAVT(e1, ":Person/age").a.v.get.map(_ ==> List( (":Person/age", 42) ))
  _ <- EAVT(e1, ":Person/age", 42).a.v.get.map(_ ==> List( (":Person/age", 42) ))
  _ <- EAVT(e1, ":Person/age", 42, t1).a.v.get.map(_ ==> List( (":Person/age", 42) ))
} yield ()
```
Index attributes available:
- e - Entity id (Long)
- a - Full attribute name like ":Person/name" (String)
- v - Value of Datoms (Any)
- t - Transaction pointer (Long/Int)
- tx - Transaction entity id (Long)
- txInstant - Transaction wall clock time (java.util.Date)
- op - Operation status: assertion (true) / retraction (false)
Note
The Molecule Index API's don't allow returning the whole Index/the whole database. So omitting arguments constructing the Index object (like EAVT.e.a.v.t.get) will throw an exception.
Please use Datomics API if you need to return the whole database Index:
conn.db.datoms(datomic.Database.EAVT)

trait GenericLog extends AnyRef

Log interface.

Log interface.

Datomic's database log is a recording of all transaction data in historic order, organized for efficient access by transaction.

Instantiate Log object with tx range arguments between from (inclusive) and until (exclusive), and add Log attributes to be returned as tuples of data:

for {
  // Data from transaction t1 until t4 (exclusive)
  _ <- Log(Some(t1), Some(t4)).t.e.a.v.op.get.map(_ ==> List(
    (t1, e1, ":Person/name", "Ben", true),
    (t1, e1, ":Person/age", 41, true),

    (t2, e2, ":Person/name", "Liz", true),
    (t2, e2, ":Person/age", 37, true),

    (t3, e1, ":Person/age", 41, false),
    (t3, e1, ":Person/age", 42, true)
  ))

  // If `from` is None, the range starts from the beginning
  _ <- Log(None, Some(t3)).v.e.t.get.map(_ ==> List(
    (t1, e1, ":Person/name", "Ben", true),
    (t1, e1, ":Person/age", 41, true),

    (t2, e2, ":Person/name", "Liz", true),
    (t2, e2, ":Person/age", 37, true)

    // t3 not included
  ))

  // If `until` is None, the range goes to the end
  _ <- Log(Some(t2), None).v.e.t.get.map(_ ==> List(
    // t1 not included

    (t2, e2, ":Person/name", "Liz", true),
    (t2, e2, ":Person/age", 37, true),

    (t3, e1, ":Person/age", 41, false),
    (t3, e1, ":Person/age", 42, true)
  ))
} yield ()

Log attributes available:

e - Entity id (Long)
a - Full attribute name like ":Person/name" (String)
v - Value of Datoms (Any)
t - Transaction pointer (Long/Int)
tx - Transaction entity id (Long)
txInstant - Transaction wall clock time (java.util.Date)
op - Operation status: assertion (true) / retraction (false)

Note: Contrary to the Datomic Log which is map of individual transactions the Molecule Log implementation is flattened to be one continuous list of transaction data. This is to have a transparent unified return type as all other molecules returning data. Data can always be grouped if needed.

trait GenericSchema extends AnyRef
Container for Schema object.
Container for Schema object.
Some Datomic types map to two Scala types:
Datomic/Scala types:
- string - String
- boolean - Boolean
- long - Int, Long
- float - Double
- double - Double
- bigint - BigInt
- bigdec - BigDecimal
- instant - java.util.Date
- uuid - java.util.UUID
- uri - java.net.URI
- ref - Long
trait GenericVAET extends AnyRef
VAET reverse Index.
VAET reverse Index.
"The VAET index contains all and only datoms whose attribute has a :db/valueType of :db.type/ref. This is also known as the reverse index, since it allows efficient navigation of relationships in reverse." (from Datomic documentation)
Access the VAET Index in Molecule by instantiating a VAET object with one or more arguments and then add generic attributes:
```
for {
  // Say we have 3 entities pointing to one entity:
  _ <- Release.e.name.Artists.e.name.get.map(_ ==> List(
    (r1, "Abbey Road", a1, "The Beatles"),
    (r2, "Magical Mystery Tour", a1, "The Beatles"),
    (r3, "Let it be", a1, "The Beatles"),
  ))

  // .. then we can get the reverse relationships with the VAET Index:
  _ <- VAET(a1).v.a.e.get.map(_ ==> List(
    (a1, ":Release/artists", r1),
    (a1, ":Release/artists", r2),
    (a1, ":Release/artists", r3),
  ))

  // Narrow search with multiple arguments
  _ <- VAET(a1, ":Release/artist").e.get.map(_ ==> List(r1, r2, r3))
  _ <- VAET(a1, ":Release/artist", r2).e.get.map(_ ==> List(r2))
  _ <- VAET(a1, ":Release/artist", r2, t7).e.get.map(_ ==> List(r2))
} yield ()
```
Index attributes available:
- e - Entity id (Long)
- a - Full attribute name like ":Person/name" (String)
- v - Value of Datoms (Any)
- t - Transaction pointer (Long/Int)
- tx - Transaction entity id (Long)
- txInstant - Transaction wall clock time (java.util.Date)
- op - Operation status: assertion (true) / retraction (false)
Note
The Molecule Index API's don't allow returning the whole Index/the whole database. So omitting arguments constructing the Index object (like VAET.v.a.e.t.get) will throw an exception.
Please use Datomics API if you need to return the whole database Index:
conn.db.datoms(datomic.Database.VAET)

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