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Brendan Clement
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The existing docs have 254 findings from our shared Vale rules. Contributors would otherwise inherit these when editing the same lines. Clean up the prose across 80 pages: correct product names and a repeated word, simplify a few phrases, and replace dashes with punctuation that fits each sentence. The pinned Vale scan now reports zero findings, with no suppressions.
86 lines
3.0 KiB
Plaintext
86 lines
3.0 KiB
Plaintext
---
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title: "Operators and literals"
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sidebarTitle: "Operators"
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description: "Comparison, logical and arithmetic operators, literals, and precedence."
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icon: plus-minus
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keywords: ["operators", "literals", "precedence", "null", "cast", "interval"]
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---
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<Badge color="red">Enterprise</Badge> [SQL runs in LanceDB Enterprise.](/sql)
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LanceDB uses DataFusion's SQL operators. This page describes comparison,
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logical and arithmetic operators, literal values, type conversions and
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operator precedence.
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## Comparison {#comparison}
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| --- | --- |
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| `=` `!=` `<>` `<` `<=` `>` `>=` | ordinary comparison |
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| `IS NULL` / `IS NOT NULL` | null test (`= NULL` is never true) |
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| `IS DISTINCT FROM` | comparison that treats null as a value |
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| `BETWEEN a AND b` | inclusive range |
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| `IN (...)` | set membership |
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| `LIKE` / `ILIKE` | pattern match, `%` and `_` |
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| `~` `~*` `!~` | regular expression match |
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<Note>
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For keyword matching on a text column, [`contains_tokens`](/sql/scalar-functions#contains-tokens)
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is index-accelerated where `LIKE` is not. Reach for `LIKE` only when you need
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its wildcard semantics.
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</Note>
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## Logical {#logical}
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`AND`, `OR`, `NOT`. Three-valued: a comparison against null is **unknown**, and
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`NOT unknown` is still unknown. A `WHERE` clause keeps only rows where the
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predicate is true, so unknown behaves like false there, but not inside `NOT
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IN`, which is the usual place this bites. See
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[Subqueries](/sql/dql/subqueries#in-exists).
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## Arithmetic {#arithmetic}
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`+` `-` `*` `/` `%`, with the usual precedence. String concatenation is `||`.
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<Warning>
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Arithmetic over a vector column is **list** arithmetic, not scalar arithmetic:
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a vector is a `FixedSizeList<Float32>`. When the operation you want is a
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similarity comparison, use [vector search](/search/vector-search); whether SQL
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can express it [depends on the Enterprise server version](/basics/sql#no-vector-sql).
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</Warning>
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## Literals {#literals}
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| --- | --- |
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| String | `'text'`, with a doubled quote to escape: `'it''s'` |
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| Number | `42`, `3.14` |
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| Boolean | `TRUE`, `FALSE` |
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| Null | `NULL` |
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| Date / timestamp | `DATE '2026-01-01'`, `TIMESTAMP '2026-01-01 12:00:00'` |
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| Interval | `INTERVAL '7 days'` |
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| Array | `[1, 2, 3]` |
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Identifiers are quoted with double quotes when they need to be (a reserved word
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or a name with mixed case): `SELECT "order" FROM "MyTable"`.
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## Casting {#casting}
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```sql
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SELECT CAST(identifier AS VARCHAR) AS with_cast, identifier::VARCHAR AS with_colons
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FROM documents
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```
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Both forms work. Give each its own alias when one projection uses both: they
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produce the same expression name, and a projection refuses two columns with
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one name. `TRY_CAST` returns null instead of erroring on a value that
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will not convert, which is the one to use over a column you do not control.
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## Precedence {#precedence}
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Highest to lowest: `::` → unary `-` → `* / %` → `+ -` → `||` → comparison →
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`IS` → `NOT` → `AND` → `OR`.
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Parenthesize anything mixing `AND` and `OR`. `a OR b AND c` is `a OR (b AND c)`,
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which is rarely what was meant.
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