pyaccesskit.schema.queries¶

pyaccesskit.schema.queries ¶

Saved query specifications and Access SQL helpers.

Access rewrites SQL when it saves a query (keywords upper-cased, one clause per line, a trailing ;, DELETE becoming DELETE *...). :func:sql_equivalent compares SQL modulo those cosmetic changes, which is what change detection needs.

MAX_SQL_LENGTH `module-attribute` ¶

MAX_SQL_LENGTH = 64000

Approximate Access limit on the length of a SQL statement.

DAO_QUERY_KINDS `module-attribute` ¶

DAO_QUERY_KINDS: dict[int, QueryKind] = {
    0: QueryKind.SELECT,
    16: QueryKind.CROSSTAB,
    32: QueryKind.DELETE,
    48: QueryKind.UPDATE,
    64: QueryKind.APPEND,
    80: QueryKind.MAKE_TABLE,
    96: QueryKind.DDL,
    112: QueryKind.PASS_THROUGH,
    128: QueryKind.UNION,
    144: QueryKind.PASS_THROUGH_BULK,
    160: QueryKind.COMPOUND,
    224: QueryKind.PROCEDURE,
    240: QueryKind.ACTION,
}

DAO QueryDefTypeEnum values (verified against the ACEDAO type library) → :class:QueryKind.

PassThroughOptions ¶

Bases: SpecModel

Settings of an ODBC pass-through query.

Attributes:

Name	Type	Description
`connect`	`str`	ODBC connection string; must start with `ODBC;`.
`returns_records`	`bool`	Whether the statement returns rows.
`timeout`	`int`	ODBC timeout in seconds (0 = no timeout).

QuerySpec ¶

Bases: SpecModel

A saved query (Access QueryDef).

Attributes:

Name	Type	Description
`name`	`str`	Query name (tables and queries share one namespace).
`sql`	`str`	The SQL text (Access SQL, or the server's dialect for pass-through queries).
`description`	`str \| None`	Query Description property.
`pass_through`	`PassThroughOptions \| None`	Set for ODBC pass-through queries.

kind `property` ¶

kind: QueryKind

The query kind as implied by the SQL text (Access reports the authoritative kind after saving).

normalized ¶

normalized() -> QuerySpec

Canonical form (SQL line endings normalized to CRLF, as Access stores them).

normalize_sql ¶

normalize_sql(sql: str) -> str

A canonical single-line form of sql for comparisons.

Whitespace is collapsed and dropped around punctuation, words and bracketed identifiers are upper-cased (Access identifiers are case-insensitive), string and date literals are preserved, trailing semicolons are removed, and Access's DELETE * FROM rewrite is undone.

sql_equivalent ¶

sql_equivalent(left: str, right: str) -> bool

Whether two SQL texts differ only cosmetically (see :func:normalize_sql).

detect_query_kind ¶

detect_query_kind(
    sql: str, *, pass_through: bool = False
) -> QueryKind

Infer the kind of query from its SQL text (used before Access has classified a saved query).

pyaccesskit.schema.queries¶