Packages

  • package root

    Documentation/API for the Molecule library - a meta DSL for the Datomic database.

    Manual | scalamolecule.org | Github | Forum

    Definition Classes
    root
  • package molecule

    Molecule library - a Scala meta-DSL for the Datomic database.

    Molecule library - a Scala meta-DSL for the Datomic database.

    See api package for various api imports to start using Molecule.

    Sub-packages

    api Molecule API.
    ast Internal Molecule ASTs.
    boilerplate Internal interfaces for auto-generated DSL boilerplate code.
    composition    Builder methods to compose molecules.
    exceptions Exceptions thrown by Molecule.
    expression Attribute expressions and operations.
    facade Molecule facades to Datomic.
    factory Implicit macro methods `m` to instantiate molecules from custom DSL molecule constructs.
    input Input molecules awaiting input.
    macros Internal macros generating molecule code from custom DSL molecule constructs.
    generic Interfaces to generic information about datoms and Datomic database.
    ops Internal operational helpers for transforming DSL to molecule.
    schema Schema definition DSL.
    transform Internal transformers from DSL to Model/Query/Transaction.
    util Internal Java database functions for Datomic.

    Definition Classes
    root
  • package generic

    Interfaces to get generic information about data and schema.

    Interfaces to get generic information about data and schema.

    • Datom - Datom attributes in molecules
    • Log - Datoms sorted by transaction/time
    • EAVT - Datoms sorted by Entity-Attribute-Value-Transaction
    • AVET - Datoms sorted by Attribute-Value-Entity-Transaction
    • AEVT - Datoms sorted by Attribute-Entity-Value-Transaction
    • VAET - "Reverse index" for reverse lookup of ref types
    • Schema - Meta information about the current database schema.
    Definition Classes
    molecule
  • package datom

    Generic Datom attribute interfaces of all arities.

    Generic Datom attribute interfaces of all arities.

    "Generic attributes" are special pre-defined attributes that can be combined with custom attributes in molecules to return meta data:

    // Get id of Ben entity with `e`
    Person.e.name.get.head === (benEntityId, "Ben")
    
    // When was Ben's age updated? Using `txInstant`
    Person(benEntityId).age.txInstant.get.head === (42, <April 4, 2019>) // (Date)
    
    // With a history db we can access the transaction number `t` and
    // assertion/retraction statusses with `op`
    Person(benEntityId).age.t.op.getHistory === List(
      (41, t1, true),  // age 41 asserted in transaction t1
      (41, t2, false), // age 41 retracted in transaction t2
      (42, t2, true)   // age 42 asserted in transaction t2
    )

    Available generic attributes:

    • 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)
    Definition Classes
    generic
    See also

    Tests for more generic attribute query examples.

  • package index

    Datomic Index APIs in Molecule.

    Datomic Index APIs in Molecule.

    Datomic maintains four indexes that contain ordered sets of datoms. Each of these indexes is named based on the sort order used:

    • EAVT - Datoms sorted by Entity-Attribute-Value-Transaction
    • AVET - Datoms sorted by Attribute-Value-Entity-Transaction
    • AEVT - Datoms sorted by Attribute-Entity-Value-Transaction
    • VAET - "Reverse index" for reverse lookup of ref types

    Create an Index molecule by instantiating an Index object with one or more arguments in the order of the Index's elements. Datoms are returned as tuples of data depending of which generic attributes you add to the Index molecule:

    // Create EAVT Index molecule with 1 entity id argument
    EAVT(e1).e.a.v.t.get === List(
      (e1, ":Person/name", "Ben", t1),
      (e1, ":Person/age", 42, t2),
      (e1, ":Golf/score", 5.7, t2)
    )
    
    // Maybe we are only interested in the attribute/value pairs:
    EAVT(e1).a.v.get === List(
      (":Person/name", "Ben"),
      (":Person/age", 42),
      (":Golf/score", 5.7)
    )
    
    // Two arguments to narrow the search
    EAVT(e1, ":Person/age").a.v.get === List(
      (":Person/age", 42)
    )
    Definition Classes
    generic
    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)

    See also

    Tests for more Index query examples.

  • package schema

    Generic Schema attribute interfaces of all arities.

    Generic Schema attribute interfaces of all arities.

    The generic Schema interface provides attributes to build molecules that query the Schema structure of the current database.

    // List of attribute entity ids
    val attrIds: Seq[Long] = Schema.id.get
    
    // Attribute name elements
    Schema.a.part.ns.nsFull.attr.get === List (
      (":sales_Customer/name", "sales", "Customer", "sales_Customer", "name"),
      (":sales_Customer/name", "sales", "Customer", "sales_Customer", "name"),
      // etc..
    )
    
    // Datomic type and cardinality of attributes
    Schema.a.tpe.card.get === List (
      (":sales_Customer/name", "string", "one"),
      (":accounting_Invoice/invoiceLine", "ref", "many"),
    )
    
    // Optional docs and attribute options
    // These can be retrieved as mandatory or optional values
    Schema.a
          .index
          .doc$
          .unique$
          .fulltext$
          .isComponent$
          .noHistory$
          .get === List(
      (":sales_Customer/name",
        true,            // indexed
        "Customer name", // doc
        None,            // Uniqueness not set
        Some(true),      // Fulltext search set so that we can search for names
        None,            // Not a component
        None             // History is preserved (noHistory not set)
        ),
      (":accounting_Invoice/invoiceLine",
        true,                   // indexed
        "Ref to Invoice lines", // doc
        None,                   // Uniqueness not set
        None,                   // Fulltext search not set
        Some(true),             // Invoice is a component - owns invoice lines
        None                    // History is preserved (noHistory not set)
        ),
    )
    
    // Defined enum values
    Schema.a.enum.get.groupBy(_._1).map(g => g._1 -> g._2) === Map(
      ":Person/gender" -> List("female", "male"),
      ":Interests/sports" -> List("golf", "basket", "badminton")
    )
    
    // Schema transaction times
    Schema.t.tx.txInstant.get === List(
      (t1, tx1, <Date: 2018-11-07 09:28:10>), // Initial schema transaction
      (t2, tx2, <Date: 2019-01-12 12:43:27>), // Additional schema attribute definitions...
    )

    Apply expressions to narrow the returned selection of Schema data:

    // Namespaces in the "gen" partition (partition name tacit)
    Schema.part_("location").ns.get === List("Country", "Region", etc...)
    
    // Attributes in the "Person" namespace
    Schema.ns_("Person").attr.get === List("name", "age", "hobbies", etc...)
    
    // How many enum attributes?
    Schema.enum_.a(count).get === List(2)
    Definition Classes
    generic
    Note

    Schema attributes defined in Datomic's bootstrap process that are not related to the current database are transparently filtered out from all Schema queries.

    See also

    Tests for more Schema query examples.

  • GenericSchema
  • Schema
  • Schema_0
  • Schema_1
  • Schema_10
  • Schema_11
  • Schema_12
  • Schema_13
  • Schema_14
  • Schema_15
  • Schema_16
  • Schema_17
  • Schema_18
  • Schema_19
  • Schema_2
  • Schema_20
  • Schema_21
  • Schema_22
  • Schema_3
  • Schema_4
  • Schema_5
  • Schema_6
  • Schema_7
  • Schema_8
  • Schema_9

package schema

Generic Schema attribute interfaces of all arities.

The generic Schema interface provides attributes to build molecules that query the Schema structure of the current database.

// List of attribute entity ids
val attrIds: Seq[Long] = Schema.id.get

// Attribute name elements
Schema.a.part.ns.nsFull.attr.get === List (
  (":sales_Customer/name", "sales", "Customer", "sales_Customer", "name"),
  (":sales_Customer/name", "sales", "Customer", "sales_Customer", "name"),
  // etc..
)

// Datomic type and cardinality of attributes
Schema.a.tpe.card.get === List (
  (":sales_Customer/name", "string", "one"),
  (":accounting_Invoice/invoiceLine", "ref", "many"),
)

// Optional docs and attribute options
// These can be retrieved as mandatory or optional values
Schema.a
      .index
      .doc$
      .unique$
      .fulltext$
      .isComponent$
      .noHistory$
      .get === List(
  (":sales_Customer/name",
    true,            // indexed
    "Customer name", // doc
    None,            // Uniqueness not set
    Some(true),      // Fulltext search set so that we can search for names
    None,            // Not a component
    None             // History is preserved (noHistory not set)
    ),
  (":accounting_Invoice/invoiceLine",
    true,                   // indexed
    "Ref to Invoice lines", // doc
    None,                   // Uniqueness not set
    None,                   // Fulltext search not set
    Some(true),             // Invoice is a component - owns invoice lines
    None                    // History is preserved (noHistory not set)
    ),
)

// Defined enum values
Schema.a.enum.get.groupBy(_._1).map(g => g._1 -> g._2) === Map(
  ":Person/gender" -> List("female", "male"),
  ":Interests/sports" -> List("golf", "basket", "badminton")
)

// Schema transaction times
Schema.t.tx.txInstant.get === List(
  (t1, tx1, <Date: 2018-11-07 09:28:10>), // Initial schema transaction
  (t2, tx2, <Date: 2019-01-12 12:43:27>), // Additional schema attribute definitions...
)

Apply expressions to narrow the returned selection of Schema data:

// Namespaces in the "gen" partition (partition name tacit)
Schema.part_("location").ns.get === List("Country", "Region", etc...)

// Attributes in the "Person" namespace
Schema.ns_("Person").attr.get === List("name", "age", "hobbies", etc...)

// How many enum attributes?
Schema.enum_.a(count).get === List(2)
Source
package.scala
Note

Schema attributes defined in Datomic's bootstrap process that are not related to the current database are transparently filtered out from all Schema queries.

See also

Tests for more Schema query examples.

Linear Supertypes
AnyRef, Any

Type Members

  1. trait GenericSchema extends AnyRef

    Container for Schema object.

  2. trait Schema extends GenericNs

    Base Schema trait with attribute types shared by all arity interfaces.

  3. trait Schema_0 extends Schema with OutSchema_0[Schema_0]

    Schema interface to add first Schema attribute

  4. trait Schema_1[A] extends Schema with OutSchema_1[Schema_1, A]

    Schema interface to add second Schema attribute

  5. trait Schema_10[A, B, C, D, E, F, G, H, I, J] extends Schema with OutSchema_10[Schema_10, A, B, C, D, E, F, G, H, I, J]
  6. trait Schema_11[A, B, C, D, E, F, G, H, I, J, K] extends Schema with OutSchema_11[Schema_11, A, B, C, D, E, F, G, H, I, J, K]
  7. trait Schema_12[A, B, C, D, E, F, G, H, I, J, K, L] extends Schema with OutSchema_12[Schema_12, A, B, C, D, E, F, G, H, I, J, K, L]
  8. trait Schema_13[A, B, C, D, E, F, G, H, I, J, K, L, M] extends Schema with OutSchema_13[Schema_13, A, B, C, D, E, F, G, H, I, J, K, L, M]
  9. trait Schema_14[A, B, C, D, E, F, G, H, I, J, K, L, M, N] extends Schema with OutSchema_14[Schema_14, A, B, C, D, E, F, G, H, I, J, K, L, M, N]
  10. trait Schema_15[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O] extends Schema with OutSchema_15[Schema_15, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O]
  11. trait Schema_16[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P] extends Schema with OutSchema_16[Schema_16, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P]
  12. trait Schema_17[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q] extends Schema with OutSchema_17[Schema_17, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q]
  13. trait Schema_18[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R] extends Schema with OutSchema_18[Schema_18, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R]
  14. trait Schema_19[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S] extends Schema with OutSchema_19[Schema_19, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S]
  15. trait Schema_2[A, B] extends Schema with OutSchema_2[Schema_2, A, B]
  16. trait Schema_20[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T] extends Schema with OutSchema_20[Schema_20, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T]
  17. trait Schema_21[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U] extends Schema with OutSchema_21[Schema_21, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U]
  18. trait Schema_22[A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V] extends Schema with OutSchema_22[Schema_22, A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V]
  19. trait Schema_3[A, B, C] extends Schema with OutSchema_3[Schema_3, A, B, C]
  20. trait Schema_4[A, B, C, D] extends Schema with OutSchema_4[Schema_4, A, B, C, D]
  21. trait Schema_5[A, B, C, D, E] extends Schema with OutSchema_5[Schema_5, A, B, C, D, E]
  22. trait Schema_6[A, B, C, D, E, F] extends Schema with OutSchema_6[Schema_6, A, B, C, D, E, F]
  23. trait Schema_7[A, B, C, D, E, F, G] extends Schema with OutSchema_7[Schema_7, A, B, C, D, E, F, G]
  24. trait Schema_8[A, B, C, D, E, F, G, H] extends Schema with OutSchema_8[Schema_8, A, B, C, D, E, F, G, H]
  25. trait Schema_9[A, B, C, D, E, F, G, H, I] extends Schema with OutSchema_9[Schema_9, A, B, C, D, E, F, G, H, I]

Inherited from AnyRef

Inherited from Any

Ungrouped