Commit graph

133 commits

Author SHA1 Message Date
Richard Newman
74f188df9b Part 5b: rename also/instead to add_intersection and add_alternate. 2017-03-30 19:13:20 -07:00
Richard Newman
9e5c735460 Part 5: split cc.rs into a 'clauses' module.
mod.rs defines the module and ConjoiningClauses itself, complete with
methods to record facts and ask it questions.

pattern.rs, predicate.rs, resolve.rs, and or.rs include particular
functionality around accumulating certain kinds of patterns.

Only `or.rs` includes significant new code; the rest is just split.
2017-03-30 19:13:20 -07:00
Richard Newman
ce3c4f0dca Part 3: have table_for_places return a Result, not an Option. 2017-03-30 19:13:20 -07:00
Richard Newman
01ca0ae5c1 Part 2: add an EmptyBecause case for fulltext/non-string type mismatch. 2017-03-30 19:13:19 -07:00
Richard Newman
997df0b776 Part 1: introduce ColumnIntersection and ColumnAlternation.
This provides a limited form of OR and AND for column constraints, allowing
simple 'or-join' queries to be expressed on a single table alias.
2017-03-30 19:13:19 -07:00
Richard Newman
95a5326e23 Pre: move EmptyBecause into types.rs. 2017-03-30 18:03:03 -07:00
Richard Newman
8adb6d97fd Add validation for or-join. r=nalexander 2017-03-27 16:32:45 -07:00
Richard Newman
88df7b3b33 Correctly generate DISTINCT and LIMIT. (#386) r=nalexander 2017-03-22 14:02:00 -07:00
Richard Newman
5e971f3b22 Post: simplify type set narrowing. 2017-03-22 11:32:32 -07:00
Richard Newman
cb4ba9e68f Post: reorganize cc.rs. 2017-03-22 11:32:32 -07:00
Richard Newman
7024978517 Track ever-shrinking sets of types for variables, not a single type. (#381) r=nalexander 2017-03-22 11:30:16 -07:00
Richard Newman
97749833d0 Algebrize and translate numeric constraints. (#306) r=nalexander 2017-03-22 10:19:47 -07:00
Richard Newman
1c4e30a906 Pre: switch to taking Patterns by move, not by reference, when algebrizing. 2017-03-22 10:14:15 -07:00
Richard Newman
f5aa6b2c2c Pre: add mentat_query_algebrizer::errors. 2017-03-22 10:14:15 -07:00
Richard Newman
d8d36140a9 Pre: add tests for CC constraint intersection.
Also add a failing test for #373.
2017-03-22 10:14:15 -07:00
Richard Newman
fe307f8b7a Pre: remove dead code in cc.rs. 2017-03-22 10:13:58 -07:00
Richard Newman
3d66cb5d0f Pre: move query algebrizer types to their own file. 2017-03-22 10:13:45 -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
Richard Newman
70e5759b5f Ensure that variable bindings are used when selecting a table. r=nalexander,etoop
For queries like

```edn
[:find ?x :where [?x _ "hello"]]
[:find [?v ...] :where [_ ?a ?v]]
```

we'll query `all_datoms` to handle fulltext strings, which is expensive.

If `?a` is bound, we can avoid this — resolve any keyword binding,
ensure that the value is an attribute, and use the appropriate table.
2017-03-14 13:47:22 +00:00
Richard Newman
6109a63249 Support input bindings in ConjoiningClauses. r=nalexander 2017-03-10 19:01:56 -08:00
Richard Newman
bf38105fef (#362) Part 4: handle unknown attributes by expanding type codes. r=nalexander
Also, don't run any SQL at all if an algebrized query is known to return no results.
2017-03-08 17:44:27 -08:00
Richard Newman
b5867e9131 (#362) Part 3: implement querying against simple keywords. r=nalexander 2017-03-08 17:44:19 -08:00
Richard Newman
ce3a9bdf87 (#362) Part 2: use constrain_attribute. r=nalexander 2017-03-08 17:44:11 -08:00
Richard Newman
8935d6a8a5 (#362) Part 1: if a variable's type becomes known, don't extract it. r=nalexander
This is necessary because we process patterns sequentially; a later
pattern might tell us the type of a variable (e.g., by having a
constant attribute), at which point we can do less work.
2017-03-08 17:44:00 -08:00
Richard Newman
e898df8842 Implement basic query limits. (#361) r=nalexander 2017-03-08 17:41:42 -08:00
Richard Newman
70b112801c Implement projection and querying. (#353) r=nalexander
* Add a failing test for EDN parsing '…'.
* Expose a SQLValueType trait to get value_type_tag values out of a ValueType.
* Add accessors to FindSpec.
* Implement querying.
* Implement rudimentary projection.
* Export mentat_db::new_connection.
* Export symbols from mentat.
* Add rudimentary end-to-end query tests.
2017-03-06 14:40:10 -08:00
Richard Newman
91c75f26c8 Expand query algebrizer. r=nalexander 2017-02-23 18:39:49 -08:00
Joe Walker
60b2e6f885 Improve Debug output for ConjoiningClauses; r=rnewman
Fixes #317, and also removes the '::' exploration of rust style
2017-02-23 14:05:56 +00:00
Richard Newman
a10f68fdb7 Mark every project as being part of the workspace. r=nalexander
This allows `cargo test --all` to work.
2017-02-20 11:04:08 -08:00
Richard Newman
a9cd9b1e87 Export symbols and string helpers from mentat_query_algebrizer. 2017-02-17 17:54:07 -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
5af7082165 Partly flesh out query algebrizer. (#243) r=nalexander 2017-02-15 16:10:59 -08:00
Richard Newman
42f03f55a2 Stub out query algebrizer. 2017-02-15 16:01:22 -08:00