Avoid unnecessary executemany subbatching#1479
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This commit implements Michael's suggestion to scan as many rows of data as we can for the fast_executemany path when we are determining how many rows we can send with the same binding. It's still possible for an application to provide data in such a way that more than one invocation of SQLExecute() is required. For example, with a table containing a single VARCHAR column, you can force a separate call to SQLExecute() for each row if you alternate back and forth between rows with string values and rows with bytes values. My advice would be: "don't do that." It turns out that--because all the work to scan the rows takes place in memory--the amount of time required to scan even very large sets of values is trivial (less than a half milliseccond to scan 10,000 rows with 16 values each on my development machine) in comparison with the time needed for even a single round trip to the database. Closes mkleehammer#741
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This commit implements Michael's suggestion to scan as many rows of data as we can for the
fast_executemanypath when we are determining how many rows we can send with the same binding. It's still possible for an application to provide data in such a way that more than one invocation ofSQLExecute()is required. For example, with a table containing a singleVARCHARcolumn, you can force a separate call toSQLExecute()for each row if you alternate back and forth between rows with string values and rows with bytes values. My advice would be: "don't do that."It turns out that--because all the work to scan the rows takes place in memory--the amount of time required to scan even very large sets of values is trivial (less than a half milliseccond to scan 10,000 rows with 16 values each on my development machine) in comparison with the time needed for even a single round trip to the database.
Closes #741