Add re_data_store. It might come in handy.

crates/re_data_store/Cargo.toml

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+[package]
+name = "re_data_store"
+authors.workspace = true
+description = "An in-memory time series database for Rerun log data, based on Apache Arrow"
+edition.workspace = true
+homepage.workspace = true
+include.workspace = true
+license.workspace = true
+publish = true
+readme = "README.md"
+repository.workspace = true
+rust-version.workspace = true
+version.workspace = true
+
+[package.metadata.docs.rs]
+all-features = true
+
+
+[features]
+default = []
+
+## Enables `parking_lot`'s deadlock detection background thread.
+deadlock_detection = ["parking_lot/deadlock_detection"]
+
+## Integration with `polars`, to efficiently use the datastore with dataframes.
+polars = ["dep:polars-core", "dep:polars-ops"]
+
+
+[dependencies]
+# Rerun dependencies:
+re_error.workspace = true
+re_format = { workspace = true, features = ["arrow"] }
+re_log_types.workspace = true
+re_log.workspace = true
+re_tracing.workspace = true
+re_types_core.workspace = true
+
+# External dependencies:
+ahash.workspace = true
+arrow2 = { workspace = true, features = ["compute_concatenate"] }
+document-features.workspace = true
+indent.workspace = true
+itertools = { workspace = true }
+nohash-hasher.workspace = true
+once_cell.workspace = true
+parking_lot.workspace = true
+smallvec.workspace = true
+thiserror.workspace = true
+web-time.workspace = true
+
+# Optional dependencies:
+polars-core = { workspace = true, optional = true, features = [
+  "diagonal_concat",
+  "dtype-date",
+  "dtype-datetime",
+  "dtype-time",
+  "dtype-struct",
+  "sort_multiple",
+] }
+polars-ops = { workspace = true, optional = true, features = [
+  "dtype-date",
+  "dtype-datetime",
+  "dtype-time",
+  "dtype-struct",
+] }
+
+
+[dev-dependencies]
+re_log_types = { workspace = true, features = ["testing"] }
+re_types = { workspace = true, features = ["datagen", "testing"] }
+
+anyhow.workspace = true
+criterion.workspace = true
+mimalloc.workspace = true
+polars-core = { workspace = true, features = [
+  "diagonal_concat",
+  "dtype-date",
+  "dtype-datetime",
+  "dtype-struct",
+  "dtype-time",
+  "fmt",
+  "sort_multiple",
+] }
+rand.workspace = true
+similar-asserts.workspace = true
+tinyvec.workspace = true
+
+[lib]
+bench = false
+
+
+[[example]]
+name = "dump_dataframe"
+path = "examples/dump_dataframe.rs"
+required-features = ["polars"]
+
+[[example]]
+name = "latest_component"
+path = "examples/latest_component.rs"
+required-features = ["polars"]
+
+[[example]]
+name = "latest_components"
+path = "examples/latest_components.rs"
+required-features = ["polars"]
+
+[[example]]
+name = "range_components"
+path = "examples/range_components.rs"
+required-features = ["polars"]
+
+
+[[bench]]
+name = "arrow2"
+harness = false
+
+[[bench]]
+name = "data_store"
+harness = false
+
+[[bench]]
+name = "gc"
+harness = false
+
+[[bench]]
+name = "vectors"
+harness = false

crates/re_data_store/README.md

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+# Rerun Arrow Store
+
+Part of the [`rerun`](https://github.com/rerun-io/rerun) family of crates.
+
+[![Latest version](https://img.shields.io/crates/v/re_entity_db.svg)](https://crates.io/crates/re_entity_db)
+[![Documentation](https://docs.rs/re_entity_db/badge.svg)](https://docs.rs/re_entity_db?speculative-link)
+![MIT](https://img.shields.io/badge/license-MIT-blue.svg)
+![Apache](https://img.shields.io/badge/license-Apache-blue.svg)
+
+[Apache Arrow](https://arrow.apache.org/) is a language-independent columnar memory format for arbitrary data.
+
+The `re_data_store` crate is an in-memory time series database for Rerun log data. It is indexed by Entity path, component, timeline, and time. It supports out-of-order insertions, and fast `O(log(N))` queries.