Many files: (fc04692c) · Commits · Software / OSDI20 Artifacts / mariadb

mysql-test/r/ctype_recoding.result

+54 −0

Original line number	Diff line number	Diff line
		@@ -186,3 +186,57 @@ select * from t1 where a=_latin1'
		ERROR HY000: Illegal mix of collations (cp1251_general_ci,IMPLICIT) and (latin1_swedish_ci,COERCIBLE) for operation '='
		drop table t1;
		set names latin1;
		set names koi8r;
		create table t1 (c1 char(10) character set cp1251);
		insert into t1 values ('');
		select c1 from t1 where c1 between '' and '';
		c1

		select ifnull(c1,''), ifnull(null,c1) from t1;
		ifnull(c1,'') ifnull(null,c1)

		select if(1,c1,''), if(0,c1,'') from t1;
		if(1,c1,'') if(0,c1,'')

		select coalesce('',c1), coalesce(null,c1) from t1;
		coalesce('',c1) coalesce(null,c1)

		select least(c1,''), greatest(c1,'') from t1;
		least(c1,'') greatest(c1,'')

		select locate(c1,''), locate('',c1) from t1;
		locate(c1,'') locate('',c1)
		1 1
		select field(c1,''),field('',c1) from t1;
		field(c1,'') field('',c1)
		1 1
		select concat(c1,''), concat('',c1) from t1;
		concat(c1,'') concat('',c1)

		select concat_ws(c1,'',''), concat_ws('',c1,'') from t1;
		concat_ws(c1,'','') concat_ws('',c1,'')

		select replace(c1,'',''), replace('',c1,'') from t1;
		replace(c1,'','') replace('',c1,'')

		select substring_index(c1,'',2) from t1;
		substring_index(c1,'',2)

		select elt(1,c1,''),elt(1,'',c1) from t1;
		elt(1,c1,'') elt(1,'',c1)

		select make_set(3,c1,''), make_set(3,'',c1) from t1;
		make_set(3,c1,'') make_set(3,'',c1)
		, ,
		select insert(c1,1,2,''),insert('',1,2,c1) from t1;
		insert(c1,1,2,'') insert('',1,2,c1)

		select trim(c1 from ''),trim('' from c1) from t1;
		trim(c1 from '') trim('' from c1)

		select lpad(c1,3,''), lpad('',3,c1) from t1;
		lpad(c1,3,'') lpad('',3,c1)

		select rpad(c1,3,''), rpad('',3,c1) from t1;
		rpad(c1,3,'') rpad('',3,c1)

mysql-test/t/ctype_recoding.test

+26 −0

Original line number	Diff line number	Diff line
		@@ -153,3 +153,29 @@ select * from t1 where a=_latin1'
		drop table t1;
		set names latin1;

		#
		# Check more automatic conversion
		#
		set names koi8r;
		create table t1 (c1 char(10) character set cp1251);
		insert into t1 values ('');
		select c1 from t1 where c1 between '' and '';
		select ifnull(c1,''), ifnull(null,c1) from t1;
		select if(1,c1,''), if(0,c1,'') from t1;
		select coalesce('',c1), coalesce(null,c1) from t1;
		select least(c1,''), greatest(c1,'') from t1;
		select locate(c1,''), locate('',c1) from t1;
		select field(c1,''),field('',c1) from t1;
		select concat(c1,''), concat('',c1) from t1;
		select concat_ws(c1,'',''), concat_ws('',c1,'') from t1;
		select replace(c1,'',''), replace('',c1,'') from t1;
		select substring_index(c1,'',2) from t1;
		select elt(1,c1,''),elt(1,'',c1) from t1;
		select make_set(3,c1,''), make_set(3,'',c1) from t1;
		select insert(c1,1,2,''),insert('',1,2,c1) from t1;
		select trim(c1 from ''),trim('' from c1) from t1;
		select lpad(c1,3,''), lpad('',3,c1) from t1;
		select rpad(c1,3,''), rpad('',3,c1) from t1;
		# TODO
		#select case c1 when '' then '' when '' then '' else 'c' end from t1;
		#select export_set(5,c1,''), export_set(5,'',c1) from t1;

sql/item.cc

+41 −0

Original line number	Diff line number	Diff line
		@@ -205,6 +205,41 @@ bool Item::eq(const Item *item, bool binary_cmp) const
		}


		Item Item::safe_charset_converter(CHARSET_INFO tocs)
		{
		/*
		Don't allow automatic conversion to non-Unicode charsets,
		as it potentially loses data.
		*/
		if (!(tocs->state & MY_CS_UNICODE))
		return NULL; // safe conversion is not possible
		return new Item_func_conv_charset(this, tocs);
		}


		Item Item_string::safe_charset_converter(CHARSET_INFO tocs)
		{
		Item_string *conv;
		uint conv_errors;
		String tmp, cstr, *ostr= val_str(&tmp);
		cstr.copy(ostr->ptr(), ostr->length(), ostr->charset(), tocs, &conv_errors);
		if (conv_errors \|\| !(conv= new Item_string(cstr.ptr(), cstr.length(),
		cstr.charset(),
		collation.derivation)))
		{
		/*
		Safe conversion is not possible (or EOM).
		We could not convert a string into the requested character set
		without data loss. The target charset does not cover all the
		characters from the string. Operation cannot be done correctly.
		*/
		return NULL;
		}
		conv->str_value.copy();
		return conv;
		}


		bool Item_string::eq(const Item *item, bool binary_cmp) const
		{
		if (type() == item->type())
		@@ -723,6 +758,12 @@ String Item_null::val_str(String str)
		}


		Item Item_null::safe_charset_converter(CHARSET_INFO tocs)
		{
		collation.set(tocs);
		return this;
		}

		/********************* Item_param related ****************************/

		/*

sql/item.h

+15 −3

Original line number	Diff line number	Diff line
		@@ -39,13 +39,22 @@ enum Derivation

		/*
		Flags for collation aggregation modes:
		allow conversion to a superset
		allow conversion of a coercible value (i.e. constant).
		MY_COLL_ALLOW_SUPERSET_CONV - allow conversion to a superset
		MY_COLL_ALLOW_COERCIBLE_CONV - allow conversion of a coercible value
		(i.e. constant).
		MY_COLL_ALLOW_CONV - allow any kind of conversion
		(combintion of the above two)
		MY_COLL_DISALLOW_NONE - don't allow return DERIVATION_NONE
		(e.g. when aggregating for comparison)
		MY_COLL_CMP_CONV - combination of MY_COLL_ALLOW_CONV
		and MY_COLL_DISALLOW_NONE
		*/

		#define MY_COLL_ALLOW_SUPERSET_CONV 1
		#define MY_COLL_ALLOW_COERCIBLE_CONV 2

		#define MY_COLL_ALLOW_CONV 3
		#define MY_COLL_DISALLOW_NONE 4
		#define MY_COLL_CMP_CONV 7

		class DTCollation {
		public:
		@@ -302,6 +311,7 @@ class Item {
		Field tmp_table_field_from_field_type(TABLE table);

		virtual Item neg_transformer(THD thd) { return NULL; }
		virtual Item safe_charset_converter(CHARSET_INFO tocs);
		void delete_self()
		{
		cleanup();
		@@ -447,6 +457,7 @@ class Item_null :public Item
		Item *new_item() { return new Item_null(name); }
		bool is_null() { return 1; }
		void print(String *str) { str->append("NULL", 4); }
		Item safe_charset_converter(CHARSET_INFO tocs);
		};


		@@ -717,6 +728,7 @@ class Item_string :public Item
		return new Item_string(name, str_value.ptr(),
		str_value.length(), &my_charset_bin);
		}
		Item safe_charset_converter(CHARSET_INFO tocs);
		String *const_string() { return &str_value; }
		inline void append(char *str, uint length) { str_value.append(str, length); }
		void print(String *str);

sql/item_cmpfunc.cc

+9 −87

Original line number	Diff line number	Diff line
		@@ -173,89 +173,11 @@ void Item_bool_func2::fix_length_and_dec()
		if (!args[0] \|\| !args[1])
		return;

		/*
		We allow to apply automatic character set conversion in some cases.
		The conditions when conversion is possible are:
		- arguments A and B have different charsets
		- A wins according to coercibility rules
		(i.e. a column is stronger than a string constant,
		an explicit COLLATE clause is stronger than a column)
		- character set of A is either superset for character set of B,
		or B is a string constant which can be converted into the
		character set of A without data loss.

		If all of the above is true, then it's possible to convert
		B into the character set of A, and then compare according
		to the collation of A.
		*/

		uint32 dummy_offset;
		DTCollation coll;

		if (args[0]->result_type() == STRING_RESULT &&
		args[1]->result_type() == STRING_RESULT &&
		String::needs_conversion(0, args[0]->collation.collation,
		args[1]->collation.collation,
		&dummy_offset) &&
		!coll.set(args[0]->collation, args[1]->collation,
		MY_COLL_ALLOW_SUPERSET_CONV \|
		MY_COLL_ALLOW_COERCIBLE_CONV))
		{
		Item* conv= 0;
		Item_arena *arena= thd->current_arena, backup;
		uint strong= coll.strong;
		uint weak= strong ? 0 : 1;
		/*
		In case we're in statement prepare, create conversion item
		in its memory: it will be reused on each execute.
		*/
		if (arena->is_stmt_prepare())
		thd->set_n_backup_item_arena(arena, &backup);
		if (args[weak]->type() == STRING_ITEM)
		{
		uint conv_errors;
		String tmp, cstr, *ostr= args[weak]->val_str(&tmp);
		cstr.copy(ostr->ptr(), ostr->length(), ostr->charset(),
		args[strong]->collation.collation, &conv_errors);
		if (conv_errors)
		{
		/*
		We could not convert a string into the character set
		of the stronger side of the operation without data loss.
		It can happen if we tried to combine a column with a string
		constant, and the column charset does not cover all the
		characters from the string. Operation cannot be done
		correctly. Return an error.
		*/
		my_coll_agg_error(args[0]->collation, args[1]->collation,
		func_name());
		agg_arg_charsets(coll, args, 2, MY_COLL_CMP_CONV))
		return;
		}
		conv= new Item_string(cstr.ptr(),cstr.length(),cstr.charset(),
		args[weak]->collation.derivation);
		((Item_string*)conv)->str_value.copy();
		}
		else
		{
		if (!(coll.collation->state & MY_CS_UNICODE))
		{
		/*
		Don't allow automatic conversion to non-Unicode charsets,
		as it potentially loses data.
		*/
		my_coll_agg_error(args[0]->collation, args[1]->collation,
		func_name());
		return;
		}
		conv= new Item_func_conv_charset(args[weak],
		args[strong]->collation.collation);
		conv->collation.set(args[weak]->collation.derivation);
		conv->fix_fields(thd, 0, &conv);
		}
		if (arena->is_stmt_prepare())
		thd->restore_backup_item_arena(arena, &backup);
		args[weak]= conv ? conv : args[weak];
		}

		// Make a special case of compare with fields to get nicer DATE comparisons

		@@ -871,7 +793,7 @@ void Item_func_between::fix_length_and_dec()
		return;
		agg_cmp_type(&cmp_type, args, 3);
		if (cmp_type == STRING_RESULT &&
		agg_arg_collations_for_comparison(cmp_collation, args, 3))
		agg_arg_charsets(cmp_collation, args, 3, MY_COLL_CMP_CONV))
		return;

		/*
		@@ -987,7 +909,7 @@ Item_func_ifnull::fix_length_and_dec()
		decimals=max(args[0]->decimals,args[1]->decimals);
		agg_result_type(&cached_result_type, args, 2);
		if (cached_result_type == STRING_RESULT)
		agg_arg_collations(collation, args, arg_count);
		agg_arg_charsets(collation, args, arg_count, MY_COLL_CMP_CONV);
		else if (cached_result_type != REAL_RESULT)
		decimals= 0;

		@@ -1083,7 +1005,7 @@ Item_func_if::fix_length_and_dec()
		agg_result_type(&cached_result_type, args+1, 2);
		if (cached_result_type == STRING_RESULT)
		{
		if (agg_arg_collations(collation, args+1, 2))
		if (agg_arg_charsets(collation, args+1, 2, MY_COLL_ALLOW_CONV))
		return;
		}
		else
		@@ -1354,7 +1276,7 @@ void Item_func_case::fix_length_and_dec()

		agg_result_type(&cached_result_type, agg, nagg);
		if ((cached_result_type == STRING_RESULT) &&
		agg_arg_collations(collation, agg, nagg))
		agg_arg_charsets(collation, agg, nagg, MY_COLL_ALLOW_CONV))
		return;


		@@ -1370,7 +1292,7 @@ void Item_func_case::fix_length_and_dec()
		nagg++;
		agg_cmp_type(&cmp_type, agg, nagg);
		if ((cmp_type == STRING_RESULT) &&
		agg_arg_collations_for_comparison(cmp_collation, agg, nagg))
		agg_arg_charsets(cmp_collation, agg, nagg, MY_COLL_CMP_CONV))
		return;
		}

		@@ -1477,7 +1399,7 @@ void Item_func_coalesce::fix_length_and_dec()
		set_if_bigger(decimals,args[i]->decimals);
		}
		if (cached_result_type == STRING_RESULT)
		agg_arg_collations(collation, args, arg_count);
		agg_arg_charsets(collation, args, arg_count, MY_COLL_ALLOW_CONV);
		else if (cached_result_type != REAL_RESULT)
		decimals= 0;
		}
		@@ -2423,7 +2345,7 @@ Item_func_regex::fix_fields(THD thd, TABLE_LIST tables, Item **ref)
		max_length= 1;
		decimals= 0;

		if (agg_arg_collations(cmp_collation, args, 2))
		if (agg_arg_charsets(cmp_collation, args, 2, MY_COLL_CMP_CONV))
		return 1;

		used_tables_cache=args[0]->used_tables() \| args[1]->used_tables();