Commit 2597b1aa authored by monty@hundin.mysql.fi's avatar monty@hundin.mysql.fi
Browse files

New CAST syntax 

Cleanup of multi-table-delete in sql_yacc.yy
Changed syntax of MAXIMUM QUERIES PER HOUR to MAX_QUERIES_PER_HOUR to
not get too many reserved words.
parent b0ea238d

Docs/manual.texi

+77 −39
Original line number Diff line number Diff line
@@ -22119,10 +22119,10 @@ is @code{localhost}. 
Lock all tables before starting the dump.  The tables are locked with

@code{READ LOCAL} to allow concurrent inserts in the case of @code{MyISAM}

tables.

@item -K, --no-disable-keys.

@item -K, --disable-keys

@code{/*!40000 ALTER TABLE tb_name DISABLE KEYS */;} and

@code{/*!40000 ALTER TABLE tb_name ENABLE KEYS */;}

will not be put in the output.

will be put in the output.

@item -n, --no-create-db

@code{CREATE DATABASE /*!32312 IF NOT EXISTS*/ db_name;} will not be put in the

output. The above line will be added otherwise, if --databases or
@@ -29434,6 +29434,7 @@ mysql> select MOD(29,9); 
* String functions::            String functions

* Numeric Functions::           Numeric Functions

* Date and time functions::     Date and time functions

* Cast Functions::              

* Other Functions::             Other Functions

* Group by functions::          Functions for Use with @code{GROUP BY} Clauses

@end menu
@@ -30662,6 +30663,8 @@ mysql> select BINARY "a" = "A"; 
        -> 0

@end example













@code{BINARY string} is a shorthand for @code{CAST(string AS BINARY)}.













@xref{Cast Functions}.















@code{BINARY} was introduced in MySQL Version 3.23.0.





























Note that in some context MySQL will not be able to use the









@@ -30685,7 +30688,6 @@ make string comparison even more flexible.













@menu















* Arithmetic functions::        Arithmetic Operations















* Mathematical functions::      Mathematical Functions













* Numerical casts::             















@end menu






































@@ -30754,7 +30756,7 @@ in a context where its result is converted to an integer!













@end table









































@node Mathematical functions, Numerical casts, Arithmetic functions, Numeric Functions













@node Mathematical functions,  , Arithmetic functions, Numeric Functions















@subsubsection Mathematical Functions















All mathematical functions return @code{NULL} in case of an error.
























@@ -31151,37 +31153,7 @@ The above happens because 10.28 is actually stored as something like













10.2799999999999999.















@end table



























@node Numerical casts,  , Mathematical functions, Numeric Functions













@subsubsection Casting numbers to signed / unsigned

























@cindex casts, SIGNED













@cindex casts, UNSIGNED

























To cast a string to a numeric value, you don't have to do anything; Just













use the string value as it would be a number:

























@example













mysql> select 1+'1';













        -> 2













@end example

























MySQL support arithmetic with both signed and unsigned 64 bit values.













If you are using an numerical operations (like @code{+}) and one of the













operands are @code{unsigned}, then the result will be unsigned.  You can













override this by using the @code{SIGNED} and @code{UNSIGNED} cast













operators, which will cast the operation to signed respective unsigned













64 bit integer.

























@example













mysql> select UNSIGNED 1-2;













        -> 18446744073709551615













mysql  select SIGNED (UNSIGNED 1-2);













        -> -1













@end example

























@code{SIGNED} and @code{UNSIGNED} where added in MySQL 4.0.2.

























@node Date and time functions, Other Functions, Numeric Functions, Functions













@node Date and time functions, Cast Functions, Numeric Functions, Functions















@subsection Date and Time Functions





























@findex date and time functions










@@ -31678,8 +31650,8 @@ will return the internal timestamp value directly, with no implicit













If you give @code{UNIX_TIMESTAMP()} a wrong or out-of-range date, it will















return 0.



























If you want to subtract @code{UNIX_TIMESTAMP()} columns,













@xref{Numerical casts}.













If you want to subtract @code{UNIX_TIMESTAMP()} columns, you may want to













cast the result to signed integers. @xref{Cast Functions}.





























@findex FROM_UNIXTIME()















@item FROM_UNIXTIME(unix_timestamp)










@@ -31731,8 +31703,74 @@ mysql> select TIME_TO_SEC('00:39:38');













@end example















@end table



























@node Cast Functions, Other Functions, Date and time functions, Functions













@subsection Cast Functions

























The syntax of the @code{CAST} function is:

























@findex CAST













@findex CONVERT

























@example













CAST(expression AS type)

























or

























CONVERT(expression,type)













@end example

























Where type is one of:













@itemize @bullet













@item













@code{BINARY}













@item













@code{DATE}













@item













@code{DATETIME}













@item













@code{SIGNED @{INTEGER@}}













@item













@code{TIME}













@item













@code{UNSIGNED @{INTEGER@}}













@end itemize

























@code{CAST()} is ANSI SQL99 syntax and @code{CONVERT()} is ODBC syntax.

























The cast function is mainly useful when you want to create a column with













a specific type in a @code{CREATE ... SELECT}:

























@example













CREATE TABLE new_table SELECT CAST('2000-01-01' AS DATE);













@end example

























@code{CAST(string AS BINARY} is the same thing as @code{BINARY string}.

























To cast a string to a numeric value, you don't normally have to do













anything; Just use the string value as it would be a number:

























@example













mysql> select 1+'1';













        -> 2













@end example

























MySQL supports arithmetic with both signed and unsigned 64 bit values.













If you are using an numerical operations (like @code{+}) and one of the













operands are @code{unsigned}, then the result will be unsigned.  You can













override this by using the @code{SIGNED} and @code{UNSIGNED} cast













operators, which will cast the operation to signed respective unsigned













64 bit integer.

























@example













mysql> select CAST(1-2 AS UNSIGNED)













        -> 18446744073709551615













mysql  select CAST(CAST(1-2 AS UNSIGNED) AS SIGNED);













        -> -1













@end example

























The @code{CAST()} and @code{CONVERT()} function was added in MySQL 4.0.2.



























@node Other Functions, Group by functions, Date and time functions, Functions













@node Other Functions, Group by functions, Cast Functions, Functions















@subsection Other Functions





























@menu










@@ -47951,7 +47989,7 @@ Our TODO section contains what we plan to have in 4.0. @xref{TODO MySQL 4.0}.



























@itemize @bullet















@item













Added cast functions @code{SIGNED} and @code{UNSIGNED}.













Added @code{CAST()} and @code{CONVERT()} functions.















@item















Changed order of how keys are created in tables.















@item

























mysql-test/r/bigint.result



+6
−6






























Original line number
Diff line number
Diff line








@@ -55,12 +55,12 @@ select min(big),max(big),max(big)-1 from t1 group by a;













min(big)	max(big)	max(big)-1















-1	9223372036854775807	9223372036854775806















drop table t1;













select UNSIGNED 1-2;













UNSIGNED 1-2













select CAST(1-2 AS UNSIGNED);













CAST(1-2 AS UNSIGNED)















18446744073709551615













select SIGNED (UNSIGNED 1-2);













SIGNED (UNSIGNED 1-2)













select CAST(CAST(1-2 AS UNSIGNED) AS SIGNED INTEGER);













CAST(CAST(1-2 AS UNSIGNED) AS SIGNED INTEGER)















-1













select UNSIGNED '-1';













UNSIGNED '-1'













select CONVERT('-1',UNSIGNED);













CONVERT('-1',UNSIGNED)















18446744073709551615
























mysql-test/r/create.result



+1
−1






























Original line number
Diff line number
Diff line








@@ -87,7 +87,7 @@ d	bigint(17)			0













e	double(18,1)			0.0	















f	bigint(17)			0	















drop table t2;













create table t2 select DATE "2001-12-29" as d, TIME "20:45:11" as t, DATETIME "2001-12-29  20:45:11" as dt;













create table t2 select CAST("2001-12-29" AS DATE) as d, CAST("20:45:11" AS TIME) as t, CAST("2001-12-29  20:45:11" AS DATETIME) as dt;















describe t2;















Field	Type	Null	Key	Default	Extra















d	date			0000-00-00	

































mysql-test/r/variables.result



+9
−0






























Original line number
Diff line number
Diff line













drop table if exists t1;















set @`test`=1,@TEST=3,@select=2,@t5=1.23456;















select @test,@`select`,@TEST,@not_used;















@test	@`select`	@TEST	@not_used









@@ -24,14 +25,22 @@ select @t1:=(@t2:=1)+@t3:=4,@t1,@t2,@t3;













select @t5;















@t5















1.23456













CREATE TABLE t1 (c_id INT(4) NOT NULL, c_name CHAR(20), c_country CHAR(3), PRIMARY KEY(c_id));













INSERT INTO t1 VALUES (1,'Bozo','USA'),(2,'Ronald','USA'),(3,'Kinko','IRE'),(4,'Mr. Floppy','GB');













SELECT @min_cid:=min(c_id), @max_cid:=max(c_id) from t1;















@min_cid:=min(c_id)	@max_cid:=max(c_id)















1	4













SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid;















c_id	c_name	c_country















1	Bozo	USA















4	Mr. Floppy	GB













SELECT * FROM t1 WHERE c_id=@min_cid OR c_id=@max_cid OR c_id=666;















c_id	c_name	c_country















1	Bozo	USA















4	Mr. Floppy	GB













ALTER TABLE t1 DROP PRIMARY KEY;













select * from t1 where c_id=@min_cid OR c_id=@max_cid;















c_id	c_name	c_country















1	Bozo	USA















4	Mr. Floppy	GB













drop table t1;
























mysql-test/t/bigint.test



+3
−3






























Original line number
Diff line number
Diff line








@@ -30,6 +30,6 @@ select min(big),max(big),max(big)-1 from t1;













select min(big),max(big),max(big)-1 from t1 group by a;















drop table t1;





























select UNSIGNED 1-2;













select SIGNED (UNSIGNED 1-2);













select UNSIGNED '-1';












select CAST(1-2 AS UNSIGNED);













select CAST(CAST(1-2 AS UNSIGNED) AS SIGNED INTEGER);













select CONVERT('-1',UNSIGNED);