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author | Igor Babaev <igor@askmonty.org> | 2010-09-23 08:10:53 -0700 |
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committer | Igor Babaev <igor@askmonty.org> | 2010-09-23 08:10:53 -0700 |
commit | b969df8bbdc6acbaf1506b52346d24306e84a48c (patch) | |
tree | b0b9eaa82a121c87f17487c57926bd9968d3ef20 /sql/field.cc | |
parent | cfbd9270243e4b429cdc26e8554bcc99690f2422 (diff) | |
parent | 709a0a131021135e9fb7a2095fcfcbc223dfb126 (diff) | |
download | mariadb-git-b969df8bbdc6acbaf1506b52346d24306e84a48c.tar.gz |
Merge of the mwl106 tree into the latest 5.3 tree.
Resolved conflicts. Adjusted some test results
Diffstat (limited to 'sql/field.cc')
-rw-r--r-- | sql/field.cc | 24 |
1 files changed, 24 insertions, 0 deletions
diff --git a/sql/field.cc b/sql/field.cc index 03d78706f95..f4e1ab20a87 100644 --- a/sql/field.cc +++ b/sql/field.cc @@ -10492,3 +10492,27 @@ Field::set_datetime_warning(MYSQL_ERROR::enum_warning_level level, uint code, field_name); } } + + +/* + @brief + Return possible keys for a field + + @details + Return bit map of keys over this field which can be used by the range + optimizer. For a field of a generic table such keys are all keys that starts + from this field. For a field of a materialized derived table/view such keys + are all keys in which this field takes a part. This is less restrictive as + keys for a materialized derived table/view are generated on the fly from + present fields, thus the case when a field for the beginning of a key is + absent is impossible. + + @return map of possible keys +*/ + +key_map Field::get_possible_keys() +{ + DBUG_ASSERT(table->pos_in_table_list); + return (table->pos_in_table_list->is_materialized_derived() ? + part_of_key : key_start); +} |