The matchinfo option may only be set to the value "fts3". Attempting to set matchinfo to anything other than "fts3" is an error. If this option is specified, then some of the extra information stored by FTS4 is omitted. This reduces the amount of disk space consumed by an FTS4 table until it is almost the same as the amount that would be used by the equivalent FTS3 table, but also means that the data accessed by passing the 'l' flag to the matchinfo() function is not available.
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