ODBC Driver for Couchbase

Build 23.0.8839

FlexibleSchemas

Whether the provider allows queries to use columns that it has not discovered.

データ型

bool

デフォルト値

false

解説

By default 本製品 will only allow queries to use columns that it has found during the metadata discovery process (see TypeDetectionScheme for details). This means that the 本製品 has the full information for each column it presents, but it also means that fields set on only a few documents may not be exposed. Disabling this option means that the 本製品 will allow you to write a query with any columns you want. If you use columns in a query that have not been discovered the 本製品 will assume that they are simple strings.

For example, the 本製品 uses column type information to automatically convert dates for comparision since Couchbase cannot natively compare dates directly. If the 本製品 detects that datecol is a date field, it can apply the STR_TO_MILLIS conversion automatically:

/* SQL */
WHERE datecol < '2020-06-12';

/* N1QL */
WHERE STR_TO_MILLIS(datecol) < STR_TO_MILLIS('2020-06-12');

When using undiscovered columns the 本製品 cannot make this type of conversion for you. You must apply any needed conversions manually to ensure that operations behave the way you want them to.

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Build 23.0.8839