Commit 26601499 authored by unknown's avatar unknown

Merge work:/my/mysql-4.0 into hundin.mysql.fi:/my/mysql-4.0

parents e0e45a24 44448acb
......@@ -1579,6 +1579,276 @@ fe 00 . .
@c @printindex fn
@node 4.1 protocol,,,
@subchapter MySQL 4.1 protocol
@node 4.1 protocol changes,,,
@section Changes to 4.0 protocol in 4.1
All basic package handling is identical to 4.0. When communication
with an old 4.0 or 3.x client we will use the old protocol.
The new things that we support with 4.1 are:
@itemize @bullet
@item
Warnings
@item
Prepared statements
@item
Binary protocol (will be much faster than the current protocol that
converts everything to strings)
@end itemize
What has changed in 4.1 are:
@itemize @bullet
@item
A lot of new field information (database, real table name etc)
@item
The 'ok' packet has more status fields
@item
The 'end' packet (send last for each result set) now contains some
extra information
@item
New protocol for prepared statements. In this case all parameters and
results will sent as binary (low-byte-first).
@end itemize
@node 4.1 field package,,,
@section 4.1 field description package
The field description package is sent as a response to a query that
contains a result set. It can be distinguished from a ok package by
the fact that the first byte can't be 0 for a field package.
@xref {4.1 ok package}.
The header package has the following structure:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 1-9 @tab Number of columns in result set (never 0)
@item 1-9 @tab Extra information sent be some command (SHOW COLUMNS
uses this to send the number of rows in the table)
@end multitable
This package is always followed by a field description set.
@xref{4.1 field desc}.
@node 4.1 field desc,,,
@section 4.1 field description result set
The field description result set contains the meta info for a result set.
@multitable @columnfractions .20 .80
@item Type @tab Comment
@item string @tab Database name
@item string @tab Table name alias (or table name if no alias)
@item string @tab Real table name
@item string @tab Alias for column name (or column name if not used)
@item 3 byte int @tab Length of column definition
@item 1 byte int @tab Enum value for field type
@item 3 byte int @tab 2 byte column flags (NOT_NULL_FLAG etc..) + 1 byte number of decimals.
@item string int @tab Default value, only set when using mysql_list_fields().
@end multitable
@node 4.1 ok package,,,
@section 4.1 ok package
The ok package is the first that is sent as an response for a query
that didn't return a result set.
The ok package has the following structure:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 1 @tab 0 ; Marker for ok package
@item 1-9 @tab Affected rows
@item 1-9 @tab Last insert id (0 if one wasn't used)
@item 2 @tab Server status; Can be used by client to check if we are inside an transaction
@item 2 @tab Warning count
@item 1-9 @tab Message length (optional)
@item xxx @tab Message (optional)
@end multitable
Size 1-9 means that the parameter is packed in to 1-9 bytes depending on
the value. (See function sql/net_pkg.cc::net_store_length).
The message is optional. For example for multi line INSERT it
contains a string for how many rows was inserted / deleted.
@node 4.1 end package,,,
@section 4.1 end package
The end package is sent as the last package for
@itemize @bullet
@item
End of field information
@item
End of parameter type information
@item
End of result set
@end itemize
The end package has the following structure:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 1 @tab 254 ; Marker for EOF package
@item 2 @tab Warning count
@item 2 @tab Status flags (For flags like SERVER_STATUS_MORE_RESULTS)
@end multitable
Note that a normal package may start with byte 254, which means
'length stored in 9 bytes'. One can different between these cases
by checking the packet length < 9 bytes (in which case it's and end
packet).
@node 4.1 error package
@section 4.1 error package.
The error package is sent when something goes wrong.
The error package has the following structure:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 1 @tab 255 Error package marker
@item 1-255 @tab Null terminated error message
@end multitable
The client/server protocol is designed in such a way that a package
can only start with 255 if it's an error package.
@node 4.1 prep init,,,
@section 4.1 prepared statement init package
This is the return package when one sends a query with the COM_PREPARE
command.
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 4 @tab Statement handler id
@item 2 @tab Number of columns in result set
@item 2 @tab Number of parameters in query
@end multitable
After this, there is a packet that contains the following for each
parameter in the query:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 2 @tab Enum value for field type. (MYSQL_TYPE_UNKNOWN if not known)
@item 2 @tab 2 byte column flags (NOT_NULL_FLAG etc)
@item 1 @tab Number of decimals
@item 4 @tab Max column length.
@end itemize
Note that the above is not yet in 4.1 but will be added this month.
As MySQL can have a parameter 'anywhere' it will in many cases not be
able to provide the optimal information for all parameters.
If number of columns, in the header package, is not 0 then the
prepared statement will contain a result set. In this case the package
is followed by a field description result set. @xref{4.1 field descr}.
@node 4.1 long data,,,
@section 4.1 long data handling
This is used by mysql_send_long_data() to set any parameter to a string
value. One can call mysql_send_long_data() multiple times for the
same parameter; The server will concatenate the results to a one big
string.
The server will not require an end package for the string.
mysql_send_long_data() is responsible updating a flag that all data
has been sent. (Ie; That the last call to mysql_send_long_data() has
the 'last_data' flag set).
This package is sent from client -> server:
@multitable @columnfractions .10 .90
@item Size @tab Comment
@item 4 @tab Statement handler
@item 2 @tab Parameter number
@item 2 @tab Type of parameter (not used at this point)
@item # @tab data (Rest of package)
@end itemize
The server will NOT send an @code{ok} or @code{error} package in
responce for this. If there is any errors (like to big string), one
will get the error when calling execute.
@node 4.1 execute,,,
@section 4.1 execute
On execute we send all parameters to the server in a COM_EXECUTE
package.
The package contains the following information:
@multitable @columnfractions .30 .70
@item Size @tab Comment
@item (param_count+7)/8 @tab Null bit map
@item 1 @tab new_parameter_bound flag. Is set to 1 for first
execute or if one has rebound the parameters.
@item 2*param_count @tab Type of parameters (only given if new_parameter_bound flag is 1)
@item # @tab Parameter data, repeated for each parameter that are
NOT NULL and not used with mysql_send_long_data().
@end itemize
The null-bit-map is for all parameters (including parameters sent with
'mysql_send_long_data). If parameter 0 is NULL, then bit 0 in the
null-bit-map should be 1 (ie: first byte should be 1)
The parameters are stored the following ways:
@multitable @columnfractions .20 .10 .70
@item Type @tab Size @tab Comment
@item tynyint @tab 1 @tab One byte integer
@item short @tab 2 @tab
@item int @tab 4 @tab
@item longlong @tab 8 @tab
@item float @tab 4 @tab
@item double @tab 8 @tab
@item string @tab 1-9 + # @tab Packed string length + string
@end multitable
The result for this will be either an ok package or a binary result
set.
@node 4.1 binary result,,,
@section 4.1 binary result set
A binary result are sent the following way.
For each result row:
@itemize
@item
null bit map with first two bits set to 01 (bit 0,1 value 1)
@item
parameter data, repeated for each not null parameter.
@end itemize
The idea with the reserving two bits in the null map is that we can
use standard error (first byte 255) and ok packages (first byte 0)
to end a result sets.
Except that the null-bit-map is shifted two steps, the server is
sending the data to the client the same way that the server is sending
bound parameters to the client. The server is always sending the data
as type given for 'column type' for respective column. It's up to the
client to convert the parameter to the requested type.
@node Fulltext Search, , protocol, Top
@chapter Fulltext Search in MySQL
......
......@@ -1654,8 +1654,8 @@ log_reset_first_header_and_checkpoint(
lsn = ut_dulint_add(start, LOG_BLOCK_HDR_SIZE);
/* Write the label of ibbackup --restore */
sprintf(hdr_buf + LOG_FILE_WAS_CREATED_BY_HOT_BACKUP, "ibbackup ");
ut_sprintf_timestamp(hdr_buf + LOG_FILE_WAS_CREATED_BY_HOT_BACKUP
sprintf((char*) hdr_buf + LOG_FILE_WAS_CREATED_BY_HOT_BACKUP, "ibbackup ");
ut_sprintf_timestamp((char*) hdr_buf + LOG_FILE_WAS_CREATED_BY_HOT_BACKUP
+ strlen("ibbackup "));
buf = hdr_buf + LOG_CHECKPOINT_1;
......
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