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1 |
| -<!-- $PostgreSQL: pgsql/doc/src/sgml/textsearch.sgml,v 1.57 2010/07/29 19:34:40 petere Exp $ --> |
| 1 | +<!-- $PostgreSQL: pgsql/doc/src/sgml/textsearch.sgml,v 1.58 2010/08/20 13:59:45 tgl Exp $ --> |
2 | 2 |
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3 | 3 | <chapter id="textsearch">
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4 | 4 | <title>Full Text Search</title>
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@@ -3270,7 +3270,7 @@ CREATE INDEX <replaceable>name</replaceable> ON <replaceable>table</replaceable>
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3270 | 3270 | (<productname>PostgreSQL</productname> does this automatically when needed.)
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3271 | 3271 | GiST indexes are lossy because each document is represented in the
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3272 | 3272 | index by a fixed-length signature. The signature is generated by hashing
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3273 |
| - each word into arandom bit in an n-bit string, with all these bits OR-ed |
| 3273 | + each word into asingle bit in an n-bit string, with all these bits OR-ed |
3274 | 3274 | together to produce an n-bit document signature. When two words hash to
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3275 | 3275 | the same bit position there will be a false match. If all words in
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3276 | 3276 | the query have matches (real or false) then the table row must be
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