WL#1173: better cost estimation in find_best for Full-Text
Affects: Server-4.1 — Status: Un-Assigned — Priority: Medium
Optimizer should not ALWAYS prefer full-text index. First, index search cost is not 0 in boolean mode. Second, in NL mode only index search cost is 0, but not row retrieval cost. And the latter can easily be much larger than total cost of using some other - high selectivity - index.
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