Commit 705d5066 authored by unknown's avatar unknown
Browse files

Move collation aggregation with superset conversion code 

from Item_bool_func2 into DTCollation to make it reusable
for other types of items.
parent acd13219

sql/item.cc

+28 −2
Original line number Diff line number Diff line
@@ -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); 

        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

  {

sql/item.h

+9 −3
Original line number Diff line number Diff line
@@ -41,16 +41,22 @@ class DTCollation { 
public:

  CHARSET_INFO     *collation;

  enum Derivation derivation;

  uint nagg;    // Total number of aggregated collations.

  uint strong;  // Number of the strongest collation.

  

  DTCollation()

  {

    collation= &my_charset_bin;

    derivation= DERIVATION_NONE;

    nagg= 0;

    strong= 0;

  }

  DTCollation(CHARSET_INFO *collation_arg, Derivation derivation_arg)

  {

    collation= collation_arg;

    derivation= derivation_arg;

    nagg= 0;

    strong= 0;

  }

  void set(DTCollation &dt)

  {
@@ -66,9 +72,9 @@ class DTCollation { 
  { collation= collation_arg; }

  void set(Derivation derivation_arg)

  { derivation= derivation_arg; }

  bool aggregate(DTCollation &dt);

  bool set(DTCollation &dt1, DTCollation &dt2)

  { set(dt1); return aggregate(dt2); }

  bool aggregate(DTCollation &dt, bool superset_conversion= FALSE);

  bool set(DTCollation &dt1, DTCollation &dt2, bool superset_conversion= FALSE)

  { set(dt1); return aggregate(dt2, superset_conversion); }

  const char *derivation_name() const

  {

    switch(derivation)

sql/item_cmpfunc.cc

+8 −16
Original line number Diff line number Diff line
@@ -188,25 +188,17 @@ void Item_bool_func2::fix_length_and_dec() 
  {

    uint strong= 0;

    uint weak= 0;

    DTCollation coll;



    if ((args[0]->collation.derivation < args[1]->collation.derivation) && 

    if (args[0]->result_type() == STRING_RESULT &&

        args[1]->result_type() == STRING_RESULT &&

        !my_charset_same(args[0]->collation.collation,

                         args[1]->collation.collation) &&

        (args[0]->collation.collation->state & MY_CS_UNICODE))

    {

      weak= 1;

    }

    else if ((args[1]->collation.derivation < args[0]->collation.derivation) && 

	     !my_charset_same(args[0]->collation.collation,

			      args[1]->collation.collation) &&

             (args[1]->collation.collation->state & MY_CS_UNICODE))

    {

      strong= 1;

    }

    

    if (strong || weak)

        !coll.set(args[0]->collation, args[1]->collation, TRUE))

    {

      Item* conv= 0;

      strong= coll.strong;

      weak= strong ? 0 : 1;

      if (args[weak]->type() == STRING_ITEM)

      {

        String tmp, cstr;