Fix incorrect behavior when preparing SELECT * preceded by a WITH #1179
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In stephencelis#1139 I introduced support for the `WITH` clause. My implementation contains a bug: the statement preparer doesn't produce the correct result column names for queries containing a `SELECT *` preceded by a `WITH`. For example, consider the following statement: ``` WITH temp AS ( SELECT id, email from users) SELECT * from temp ``` An error would be thrown when preparing this statement because the glob expansion procedure would try to look up the column names for the result by looking up the column names for the query `SELECT * from temp`. This does not work because `temp` is a temporary view defined in the `WITH` clause. To fix this, I modified the glob expansion procedure to include the `WITH` clause in the query used to look up the result column names.
marmphco
commented
Dec 23, 2022
| func expandGlob(_ namespace: Bool) -> (QueryType) throws -> Void { | ||
| { (queryType: QueryType) throws -> Void in | ||
| var query = type(of: queryType).init(queryType.clauses.from.name, database: queryType.clauses.from.database) | ||
| query.clauses.select = queryType.clauses.select | ||
| query.clauses.with = strip(queryType.clauses.with) |
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The strip function feels a little excessive. Doing this instead also works:
query.clauses.with = queryType.clauses.withbut the query will include things that aren't necessary for determining the result column names, like filters, sorting, and grouping.
nathanfallet
approved these changes
Dec 28, 2022
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In #1139 I introduced support for the
WITHclause. My implementation contains a bug: preparing a query containing aSELECT *preceded by aWITHcauses an error to be thrown.Consider the following statement:
An error is thrown when preparing this statement because the glob expansion procedure tries to determine the column names for the result by looking up the column names for the query
SELECT * from temp. This does not work becausetempis a temporary view defined in theWITHclause.To fix this, I modified the glob expansion procedure to include the
WITHclause in the query used to look up the result column names.