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10 commits

Author SHA1 Message Date
Richard Newman
a5023c70cb Use Rc for TypedValue, Variable, and query Ident keywords. (#395) r=nalexander
Part 1, core: use Rc for String and Keyword.
Part 2, query: use Rc for Variable.
Part 3, sql: use Rc for args in SQLiteQueryBuilder.
Part 4, query-algebrizer: use Rc.
Part 5, db: use Rc.
Part 6, query-parser: use Rc.
Part 7, query-projector: use Rc.
Part 8, query-translator: use Rc.
Part 9, top level: use Rc.
Part 10: intern Ident and IdentOrKeyword.
2017-04-02 21:38:36 -07:00
Nick Alexander
2129514e86 Support transacting :db/fulltext true attributes. Fixes #189. (#375) r=rnewman
These tests are direct translations of the Clojure tests.
2017-03-21 13:12:10 -07:00
Nick Alexander
15b4195a6e Schema alteration. Fixes #294 and #295. (#370) r=rnewman
* Pre: Don't retract :db/ident in test.

Datomic (and eventually Mentat) don't allow to retract :db/ident in
this way, so this runs afoul of future work to support mutating
metadata.

* Pre: s/VALUETYPE/VALUE_TYPE/.

This is consistent with the capitalization (which is "valueType") and
the other identifier.

* Pre: Remove some single quotes from error output.

* Part 1: Make materialized views be uniform [e a v value_type_tag].

This looks ahead to a time when we could support arbitrary
user-defined materialized views.  For now, the "idents" materialized
view is those datoms of the form [e :db/ident :namespaced/keyword] and
the "schema" materialized view is those datoms of the form [e a v]
where a is in a particular set of attributes that will become clear in
the following commits.

This change is not backwards compatible, so I'm removing the open
current (really, v2) test.  It'll be re-instated when we get to
https://github.com/mozilla/mentat/issues/194.

* Pre: Map TypedValue::Ref to TypedValue::Keyword in debug output.

* Part 3: Separate `schema_to_mutate` from the `schema` used to interpret.

This is just to keep track of the expected changes during
bootstrapping.  I want bootstrap metadata mutations to flow through
the same code path as metadata mutations during regular transactions;
by differentiating the schema used for interpretation from the schema
that will be updated I expect to be able to apply bootstrap metadata
mutations to an empty schema and have things like materialized views
created (using the regular code paths).

This commit has been re-ordered for conceptual clarity, but it won't
compile because it references the metadata module.  It's possible to
make it compile -- the functionality is there in the schema module --
but it's not worth the rebasing effort until after review (and
possibly not even then, since we'll squash down to a single commit to
land).

* Part 2: Maintain entids separately from idents.

In order to support historical idents, we need to distinguish the
"current" map from entid -> ident from the "complete historical" map
ident -> entid.  This is what Datomic does; in Datomic, an ident is
never retracted (although it can be replaced).  This approach is an
important part of allowing multiple consumers to share a schema
fragment as it migrates forward.

This fixes a limitation of the Clojure implementation, which did not
handle historical idents across knowledge base close and re-open.

The "entids" materialized view is naturally a slice of the "datoms"
table.  The "idents" materialized view is a slice of the
"transactions" table.  I hope that representing in this way, and
casting the problem in this light, might generalize to future
materialized views.

* Pre: Add DiffSet.

* Part 4: Collect mutations to a `Schema`.

I haven't taken your review comment about consuming AttributeBuilder
during each fluent function.  If you read my response and still want
this, I'm happy to do it in review.

* Part 5: Handle :db/ident and :db.{install,alter}/attribute.

This "loops" the committed datoms out of the SQL store and back
through the metadata (schema, but in future also partition map)
processor.  The metadata processor updates the schema and produces a
report of what changed; that report is then used to update the SQL
store.  That update includes:
- the materialized views ("entids", "idents", and "schema");
- if needed, a subset of the datoms themselves (as flags change).

I've left a TODO for handling attribute retraction in the cases that
it makes sense.  I expect that to be straight-forward.

* Review comment: Rename DiffSet to AddRetractAlterSet.

Also adds a little more commentary and a simple test.

* Review comment: Use ToIdent trait.

* Review comment: partially revert "Part 2: Maintain entids separately from idents."

This reverts commit 23a91df9c35e14398f2ddbd1ba25315821e67401.

Following our discussion, this removes the "entids" materialized
view.  The next commit will remove historical idents from the "idents"
materialized view.

* Post: Use custom Either rather than std::result::Result.

This is not necessary, but it was suggested that we might be paying an
overhead creating Err instances while using error_chain.  That seems
not to be the case, but this change shows that we don't actually use
any of the Result helper methods, so there's no reason to overload
Result.  This change might avoid some future confusion, so I'm going
to land it anyway.

Signed-off-by: Nick Alexander <nalexander@mozilla.com>

* Review comment: Don't preserve historical idents.

* Review comment: More prepared statements when updating materialized views.

* Post: Test altering :db/cardinality and :db/unique.

These tests fail due to a Datomic limitation, namely that the marker
flag :db.alter/attribute can only be asserted once for an attribute!
That is, [:db.part/db :db.alter/attribute :attribute] will only be
transacted at most once.  Since older versions of Datomic required the
:db.alter/attribute flag, I can only imagine they either never wrote
:db.alter/attribute to the store, or they handled it specially.  I'll
need to remove the marker flag system from Mentat in order to address
this fundamental limitation.

* Post: Remove some more single quotes from error output.

* Post: Add assert_transact! macro to unwrap safely.

I was finding it very difficult to track unwrapping errors while
making changes, due to an underlying Mac OS X symbolication issue that
makes running tests with RUST_BACKTRACE=1 so slow that they all time
out.

* Post: Don't expect or recognize :db.{install,alter}/attribute.

I had this all working... except we will never see a repeated
`[:db.part/db :db.alter/attribute :attribute]` assertion in the store!
That means my approach would let you alter an attribute at most one
time.  It's not worth hacking around this; it's better to just stop
expecting (and recognizing) the marker flags.  (We have all the data
to distinguish the various cases that we need without the marker
flags.)

This brings Mentat in line with the thrust of newer Datomic versions,
but isn't compatible with Datomic, because (if I understand correctly)
Datomic automatically adds :db.{install,alter}/attribute assertions to
transactions.

I haven't purged the corresponding :db/ident and schema fragments just
yet:
- we might want them back
- we might want them in order to upgrade v1 and v2 databases to the
  new on-disk layout we're fleshing out (v3?).

* Post: Don't make :db/unique :db.unique/* imply :db/index true.

This patch avoids a potential bug with the "schema" materialized view.
If :db/unique :db.unique/value implies :db/index true, then what
happens when you _retract_ :db.unique/value?  I think Datomic defines
this in some way, but I really want the "schema" materialized view to
be a slice of "datoms" and not have these sort of ambiguities and
persistent effects.  Therefore, to ensure that we don't retract a
schema characteristic and accidentally change more than we intended
to, this patch stops having any schema characteristic imply any other
schema characteristic(s).  To achieve that, I added an
Option<Unique::{Value,Identity}> type to Attribute; this helps with
this patch, and also looks ahead to when we allow to retract
:db/unique attributes.

* Post: Allow to retract :db/ident.

* Post: Include more details about invalid schema changes.

The tests use strings, so they hide the chained errors which do in
fact provide more detail.

* Review comment: Fix outdated comment.

* Review comment: s/_SET/_SQL_LIST/.

* Review comment: Use a sub-select for checking cardinality.

This might be faster in practice.

* Review comment: Put `attribute::Unique` into its own namespace.
2017-03-20 13:18:59 -07:00
Nick Alexander
1801db2a77 Convert EDN transaction tests to Rust code. Fixes #271. (#364) r=rnewman
* Pre: Order datoms deterministically in debug output.

This makes comparison much easier, and avoids a whole class of
difficult problems when introducing pattern matching with placeholder
values.

* Pre: Don't rewrite ?txN and ?msN in debug module into_edn() methods.

* Convert EDN transaction tests to Rust code. Fixes #271.

This implements
https://github.com/mozilla/mentat/issues/271#issuecomment-283125963.
I'm using the EDN pattern matching functionality
internally (extensively!), but specifically working around the tricky
edges we encountered.  This should let us implement tests quickly (and
hopefully legibly) while not requiring us to encode as much behaviour
into non-standard EDN notations.
2017-03-20 11:29:17 -07:00
Nick Alexander
dcd9bcb1ce Extract partial storage abstraction; use error-chain throughout. Fixes #328. r=rnewman (#341)
* Pre: Drop unneeded tx0 from search results.

* Pre: Don't require a schema in some of the DB code.

The idea is to separate the transaction applying code, which is
schema-aware, from the concrete storage code, which is just concerned
with getting bits onto disk.

* Pre: Only reference Schema, not DB, in debug module.

This is part of a larger separation of the volatile PartitionMap,
which is modified every transaction, from the stable Schema, which is
infrequently modified.

* Pre: Fix indentation.

* Extract part of DB to new SchemaTypeChecking trait.

* Extract part of DB to new PartitionMapping trait.

* Pre: Don't expect :db.part/tx partition to advance when tx fails.

This fails right now, because we allocate tx IDs even when we shouldn't.

* Sketch a db interface without DB.

* Add ValueParseError; use error-chain in tx-parser.

This can be simplified when
https://github.com/Marwes/combine/issues/86 makes it to a published
release, but this unblocks us for now.  This converts the `combine`
error type `ParseError<&'a [edn::Value]>` to a type with owned
`Vec<edn::Value>` collections, re-using `edn::Value::Vector` for
making them `Display`.

* Pre: Accept Borrow<Schema> instead of just &Schema in debug module.

This makes it easy to use Rc<Schema> or Arc<Schema> without inserting
&* sigils throughout the code.

* Use error-chain in query-parser.

There are a few things to point out here:

- the fine grained error types have been flattened into one crate-wide
  error type; it's pretty easy to regain the granularity as needed.

- edn::ParseError is automatically lifted to
  mentat_query_parser::errors::Error;

- we use mentat_parser_utils::ValueParser to maintain parsing error
  information from `combine`.

* Patch up top-level.

* Review comment: Only `borrow()` once.
2017-02-24 15:33:48 -08:00
Jordan Santell
a59f9583ac Store Idents as NamespacedKeywords, rather than Strings. Fixes #291. (#300)
r=ncalexander
2017-02-17 13:55:36 -08:00
Richard Newman
a87e5a3ec7 Move Schema from mentat_db to mentat_core, improve API. (#290)
* Move Schema from mentat_db to mentat_core.
* Define SchemaMap in terms of Entid, not i64.
* Add Schema::{is_attribute,identifies_attribute}.
* Add pointer to #291.
* Don't pass around 64-bit pointers to 64-bit integers.
2017-02-13 19:20:20 -08:00
Richard Newman
c111d4daff Move TypedValue into mentat_core. r=jsantell,nalexander 2017-02-08 14:20:10 -08:00
Nick Alexander
afafcd64a0 [tx] Start implementing bulk SQL insertion algorithms (#214). r=rnewman,jsantell
* Pre: Add some value conversion tests.

This is follow-up to earlier work.  Turn TypedValue::Keyword into
edn::Value::NamespacedKeyword.  Don't take a reference to
value_type_tag.

* Pre: Add repeat_values.

Requires itertools, so this commit is not stand-alone.

* Pre: Expose the first transaction ID as bootstrap::TX0.

This is handy for testing.

* Pre: Improve debug module.

* Pre: Bump rusqlite version for https://github.com/jgallagher/rusqlite/issues/211.

* Pre: Use itertools.

* Start implementing bulk SQL insertion algorithms. (#214)

This is slightly simpler re-expression of the existing Clojure
implementation.

* Post: Start generic data-driven transaction testing. (#188)

* Review comment: `use ::{SYMBOL}` instead of `use {SYMBOL}`.

* Review comment: Prefer bindings_per_statement to values_per_statement.
2017-02-08 14:04:32 -08:00
Nick Alexander
81af295948 Start installing SQL schema. (#171) r=rnewman
* Start installing the SQLite store and bootstrapping the datom store.

* Review comment: Decomplect V2_IDENTS.

* Review comment: Decomplect V2_PARTS.

* Review comment: Pre: Expose Clojure's merge on Value instances.

* Review comment: Decomplect V2_SYMBOLIC_SCHEMA.

* Review comment: Decomplect V1_STATEMENTS.

* Review comment: Prefer ? to try!.

* Review comment: Fix typos; format; add TODOs.

* Review comment: Assert that Mentat `Schema` is valid upon creation.

* Review comment: Improve conversion to and from SQL values.

This patch factors the fundamental SQL conversion maps
between (rusqlite::Value, value_type_tag) and (edn::Value, ValueType)
through a new Mentat TypedValue.  (A future patch might rename this
fundamental type mentat::Value.)

To make certain conversion functions infallible, I removed
placeholders for :db.type/{instant,uuid,uri}.  (We could panic
instead, but there's no need to do that right now.)

* Review comment: Always uses bundled SQLite in rusqlite.

This avoids (runtime) failures in Travis CI due to old SQLite
versions.  See 432966ac77.

* Review comment: Move semantics in `from_sql_value_pair`.

* Review comment: DB_EXCISE_BEFORE_T instead of ...BEFORET (no underscore).

* Review comment: Move overview notes to the Wiki.
2017-01-25 16:13:56 -08:00