diff options
Diffstat (limited to 'sql/item.cc')
| -rw-r--r-- | sql/item.cc | 30 |
1 files changed, 28 insertions, 2 deletions
diff --git a/sql/item.cc b/sql/item.cc index 2c98aad2074..e9ef3b6a763 100644 --- a/sql/item.cc +++ b/sql/item.cc @@ -265,8 +265,9 @@ CHARSET_INFO *Item::default_charset() return current_thd->variables.collation_connection; } -bool DTCollation::aggregate(DTCollation &dt) +bool DTCollation::aggregate(DTCollation &dt, bool superset_conversion) { + nagg++; if (!my_charset_same(collation, dt.collation)) { /* @@ -280,15 +281,39 @@ bool DTCollation::aggregate(DTCollation &dt) if (derivation <= dt.derivation) ; // Do nothing else - set(dt); + { + set(dt); + strong= nagg; + } } else if (dt.collation == &my_charset_bin) { if (dt.derivation <= derivation) + { set(dt); + strong= nagg; + } else ; // Do nothing } + else if (superset_conversion) + { + if (derivation < dt.derivation && + collation->state & MY_CS_UNICODE) + ; // Do nothing + else if (dt.derivation < derivation && + dt.collation->state & MY_CS_UNICODE) + { + set(dt); + strong= nagg; + } + else + { + // Cannot convert to superset + set(0, DERIVATION_NONE); + return 1; + } + } else { set(0, DERIVATION_NONE); @@ -302,6 +327,7 @@ bool DTCollation::aggregate(DTCollation &dt) else if (dt.derivation < derivation) { set(dt); + strong= nagg; } else { |