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Comment:Link the optoverview.html document to the new expridx.html document.
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SHA1: 47d33de042d07cfb8462113461708b2bda98acf7
User & Date: drh 2015-10-07 19:40:17
Context
2015-10-07
22:42
Fix a couple typos in the new docs. check-in: 255ed0fac7 user: mistachkin tags: trunk
19:40
Link the optoverview.html document to the new expridx.html document. check-in: 47d33de042 user: drh tags: trunk
19:35
Add a new documentation page that talks specifically about indexes on expressions. check-in: 8b6ed636e3 user: drh tags: trunk
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  that constraints column c, then terms that constrain columns a and b can
  be used with the index but not terms that constraint columns d through z.
  ^Similarly, index columns will not normally be used (for indexing purposes)
  if they are to the right of a 
  column that is constrained only by inequalities.
  (See the [skip-scan optimization] below for the exception.)
}







HEADING 2 {Index term usage examples} idxexamp
PARAGRAPH {
  ^(For the index above and WHERE clause like this:
}
CODE {
  ... WHERE a=5 AND b IN (1,2,3) AND c IS NULL AND d='hello'







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  that constraints column c, then terms that constrain columns a and b can
  be used with the index but not terms that constraint columns d through z.
  ^Similarly, index columns will not normally be used (for indexing purposes)
  if they are to the right of a 
  column that is constrained only by inequalities.
  (See the [skip-scan optimization] below for the exception.)
}
PARAGRAPH {
  In the case of [indexes on expressions], whenever the word "column" is
  used in the foregoing text, one can substitute "indexed expression"
  (meaning a copy of the expression that appears in the [CREATE INDEX]
  statement) and everything will work the same.
}

HEADING 2 {Index term usage examples} idxexamp
PARAGRAPH {
  ^(For the index above and WHERE clause like this:
}
CODE {
  ... WHERE a=5 AND b IN (1,2,3) AND c IS NULL AND d='hello'