Dialects¶

SQLSpec registers custom sqlglot dialects that extend built-in SQL grammars with extension-specific operators. These dialects enable the builder to parse and generate SQL that uses vendor-specific syntax (e.g., pgvector distance operators, ParadeDB search operators).

Import sqlspec.dialects to ensure all dialects are registered:

import sqlspec.dialects  # registers pgvector, paradedb, spanner, spangres

PostgreSQL Extensions¶

PGVector¶

Adds support for pgvector distance operators:

Operator	Description
`<->`	L2 (Euclidean) distance
`<#>`	Negative inner product
`<=>`	Cosine distance
`<+>`	L1 (Manhattan) distance
`<~>`	Hamming distance (binary vectors)
`<%>`	Jaccard distance (binary vectors)

ParadeDB¶

Extends PGVector with ParadeDB pg_search operators:

Operator	Description
`@@@`	BM25 full-text search
`&&&`	Boolean AND search
`\|\|\|`	Boolean OR search
`===`	Exact term match
`###`	Score/rank retrieval
`##`	Snippet/highlight retrieval
`##>`	Snippet/highlight with options

Spanner¶

class sqlspec.dialects.spanner.Spanner[source]

Bases: BigQuery

Google Cloud Spanner SQL dialect.

Tokenizer: alias of SpannerTokenizer

Generator: alias of SpannerGenerator

parse(sql, **opts)[source]

Repair CREATE TABLE statements that sqlglot still falls back to Command for.

Return type:: list[Expr | None]

SUPPORTS_COLUMN_JOIN_MARKS = False: Whether the old-style outer join (+) syntax is supported.

UNESCAPED_SEQUENCES: t.Dict[str, str] = {'\\\\': '\\', '\\a': '\x07', '\\b': '\x08', '\\f': '\x0c', '\\n': '\n', '\\r': '\r', '\\t': '\t', '\\v': '\x0b'}: Mapping of an escaped sequence (n) to its unescaped version (` `).

generator_class: alias of SpannerGenerator

tokenizer_class: alias of SpannerTokenizer

class sqlspec.dialects.spanner.Spangres[source]

Bases: Postgres

Spanner PostgreSQL-compatible dialect.

Generator: alias of SpangresGenerator

SUPPORTS_COLUMN_JOIN_MARKS = False: Whether the old-style outer join (+) syntax is supported.

generator_class: alias of SpangresGenerator

Expression Types¶

sqlspec.builder.VectorDistance(*, this, expression, metric='euclidean')[source]

Build a SQLSpec vector-distance expression.

Return type:: Operator