用于EagleEye3.0 规则集漏报和误报测试的示例项目,项目收集于github和gitee
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'\" t
.\" Title: \fBndb_desc\fR
.\" Author: [FIXME: author] [see http://docbook.sf.net/el/author]
.\" Generator: DocBook XSL Stylesheets v1.79.1 <http://docbook.sf.net/>
.\" Date: 09/06/2019
.\" Manual: MySQL Database System
.\" Source: MySQL 8.0
.\" Language: English
.\"
.TH "\FBNDB_DESC\FR" "1" "09/06/2019" "MySQL 8\&.0" "MySQL Database System"
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.nh
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.\" * MAIN CONTENT STARTS HERE *
.\" -----------------------------------------------------------------
.SH "NAME"
ndb_desc \- describe NDB tables
.SH "SYNOPSIS"
.HP \w'\fBndb_desc\ \fR\fB\fIoptions\fR\fR\ 'u
\fBndb_desc \fR\fB\fIoptions\fR\fR
.SH "DESCRIPTION"
.PP
\fBndb_desc\fR
provides a detailed description of one or more
NDB
tables\&.
Usage
.sp
.if n \{\
.RS 4
.\}
.nf
ndb_desc \-c \fIconnection_string\fR \fItbl_name\fR \-d \fIdb_name\fR [\fIoptions\fR]
ndb_desc \-c \fIconnection_string\fR \fIindex_name\fR \-d \fIdb_name\fR \-t \fItbl_name\fR
.fi
.if n \{\
.RE
.\}
.PP
Additional options that can be used with
\fBndb_desc\fR
are listed later in this section\&.
Sample Output.PP
MySQL table creation and population statements:
.sp
.if n \{\
.RS 4
.\}
.nf
USE test;
CREATE TABLE fish (
id INT(11) NOT NULL AUTO_INCREMENT,
name VARCHAR(20) NOT NULL,
length_mm INT(11) NOT NULL,
weight_gm INT(11) NOT NULL,
PRIMARY KEY pk (id),
UNIQUE KEY uk (name)
) ENGINE=NDB;
INSERT INTO fish VALUES
(NULL, \*(Aqguppy\*(Aq, 35, 2), (NULL, \*(Aqtuna\*(Aq, 2500, 150000),
(NULL, \*(Aqshark\*(Aq, 3000, 110000), (NULL, \*(Aqmanta ray\*(Aq, 1500, 50000),
(NULL, \*(Aqgrouper\*(Aq, 900, 125000), (NULL ,\*(Aqpuffer\*(Aq, 250, 2500);
.fi
.if n \{\
.RE
.\}
.PP
Output from
\fBndb_desc\fR:
.sp
.if n \{\
.RS 4
.\}
.nf
shell> \fB\&./ndb_desc \-c localhost fish \-d test \-p\fR
\-\- fish \-\-
Version: 2
Fragment type: HashMapPartition
K Value: 6
Min load factor: 78
Max load factor: 80
Temporary table: no
Number of attributes: 4
Number of primary keys: 1
Length of frm data: 337
Max Rows: 0
Row Checksum: 1
Row GCI: 1
SingleUserMode: 0
ForceVarPart: 1
PartitionCount: 2
FragmentCount: 2
PartitionBalance: FOR_RP_BY_LDM
ExtraRowGciBits: 0
ExtraRowAuthorBits: 0
TableStatus: Retrieved
Table options:
HashMap: DEFAULT\-HASHMAP\-3840\-2
\-\- Attributes \-\-
id Int PRIMARY KEY DISTRIBUTION KEY AT=FIXED ST=MEMORY AUTO_INCR
name Varchar(20;latin1_swedish_ci) NOT NULL AT=SHORT_VAR ST=MEMORY DYNAMIC
length_mm Int NOT NULL AT=FIXED ST=MEMORY DYNAMIC
weight_gm Int NOT NULL AT=FIXED ST=MEMORY DYNAMIC
\-\- Indexes \-\-
PRIMARY KEY(id) \- UniqueHashIndex
PRIMARY(id) \- OrderedIndex
uk(name) \- OrderedIndex
uk$unique(name) \- UniqueHashIndex
\-\- Per partition info \-\-
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space
0 2 2 32768 32768 0 0
1 4 4 32768 32768 0 0
NDBT_ProgramExit: 0 \- OK
.fi
.if n \{\
.RE
.\}
.PP
Information about multiple tables can be obtained in a single invocation of
\fBndb_desc\fR
by using their names, separated by spaces\&. All of the tables must be in the same database\&.
.PP
You can obtain additional information about a specific index using the
\fB\-\-table\fR
(short form:
\fB\-t\fR) option and supplying the name of the index as the first argument to
\fBndb_desc\fR, as shown here:
.sp
.if n \{\
.RS 4
.\}
.nf
shell> \fB\&./ndb_desc uk \-d test \-t fish\fR
\-\- uk \-\-
Version: 2
Base table: fish
Number of attributes: 1
Logging: 0
Index type: OrderedIndex
Index status: Retrieved
\-\- Attributes \-\-
name Varchar(20;latin1_swedish_ci) NOT NULL AT=SHORT_VAR ST=MEMORY
\-\- IndexTable 10/uk \-\-
Version: 2
Fragment type: FragUndefined
K Value: 6
Min load factor: 78
Max load factor: 80
Temporary table: yes
Number of attributes: 2
Number of primary keys: 1
Length of frm data: 0
Max Rows: 0
Row Checksum: 1
Row GCI: 1
SingleUserMode: 2
ForceVarPart: 0
PartitionCount: 2
FragmentCount: 2
FragmentCountType: ONE_PER_LDM_PER_NODE
ExtraRowGciBits: 0
ExtraRowAuthorBits: 0
TableStatus: Retrieved
Table options:
\-\- Attributes \-\-
name Varchar(20;latin1_swedish_ci) NOT NULL AT=SHORT_VAR ST=MEMORY
NDB$TNODE Unsigned [64] PRIMARY KEY DISTRIBUTION KEY AT=FIXED ST=MEMORY
\-\- Indexes \-\-
PRIMARY KEY(NDB$TNODE) \- UniqueHashIndex
NDBT_ProgramExit: 0 \- OK
.fi
.if n \{\
.RE
.\}
.PP
When an index is specified in this way, the
\fB\-\-extra\-partition\-info\fR
and
\fB\-\-extra\-node\-info\fR
options have no effect\&.
.PP
The
Version
column in the output contains the table\*(Aqs schema object version\&. For information about interpreting this value, see
\m[blue]\fBNDB Schema Object Versions\fR\m[]\&\s-2\u[1]\d\s+2\&.
.PP
Three of the table properties that can be set using
NDB_TABLE
comments embedded in
CREATE TABLE
and
ALTER TABLE
statements are also visible in
\fBndb_desc\fR
output\&. The table\*(Aqs
FRAGMENT_COUNT_TYPE
is always shown in the
FragmentCountType
column\&.
READ_ONLY
and
FULLY_REPLICATED, if set to 1, are shown in the
Table options
column\&. You can see this after executing the following
ALTER TABLE
statement in the
\fBmysql\fR
client:
.sp
.if n \{\
.RS 4
.\}
.nf
mysql> \fBALTER TABLE fish COMMENT=\*(AqNDB_TABLE=READ_ONLY=1,FULLY_REPLICATED=1\*(Aq;\fR
1 row in set, 1 warning (0\&.00 sec)
mysql> \fBSHOW WARNINGS\eG\fR
+\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+
| Level | Code | Message |
+\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+
| Warning | 1296 | Got error 4503 \*(AqTable property is FRAGMENT_COUNT_TYPE=ONE_PER_LDM_PER_NODE but not in comment\*(Aq from NDB |
+\-\-\-\-\-\-\-\-\-+\-\-\-\-\-\-+\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-\-+
1 row in set (0\&.00 sec)
.fi
.if n \{\
.RE
.\}
.PP
The warning is issued because
READ_ONLY=1
requires that the table\*(Aqs fragment count type is (or be set to)
ONE_PER_LDM_PER_NODE_GROUP;
NDB
sets this automatically in such cases\&. You can check that the
ALTER TABLE
statement has the desired effect using
SHOW CREATE TABLE:
.sp
.if n \{\
.RS 4
.\}
.nf
mysql> \fBSHOW CREATE TABLE fish\eG\fR
*************************** 1\&. row ***************************
Table: fish
Create Table: CREATE TABLE `fish` (
`id` int(11) NOT NULL AUTO_INCREMENT,
`name` varchar(20) NOT NULL,
`length_mm` int(11) NOT NULL,
`weight_gm` int(11) NOT NULL,
PRIMARY KEY (`id`),
UNIQUE KEY `uk` (`name`)
) ENGINE=ndbcluster DEFAULT CHARSET=latin1
COMMENT=\*(AqNDB_TABLE=READ_BACKUP=1,FULLY_REPLICATED=1\*(Aq
1 row in set (0\&.01 sec)
.fi
.if n \{\
.RE
.\}
.PP
Because
FRAGMENT_COUNT_TYPE
was not set explicitly, its value is not shown in the comment text printed by
SHOW CREATE TABLE\&.
\fBndb_desc\fR, however, displays the updated value for this attribute\&. The
Table options
column shows the binary properties just enabled\&. You can see this in the output shown here (emphasized text):
.sp
.if n \{\
.RS 4
.\}
.nf
shell> \fB\&./ndb_desc \-c localhost fish \-d test \-p\fR
\-\- fish \-\-
Version: 4
Fragment type: HashMapPartition
K Value: 6
Min load factor: 78
Max load factor: 80
Temporary table: no
Number of attributes: 4
Number of primary keys: 1
Length of frm data: 380
Max Rows: 0
Row Checksum: 1
Row GCI: 1
SingleUserMode: 0
ForceVarPart: 1
PartitionCount: 1
FragmentCount: 1
\fIFragmentCountType: ONE_PER_LDM_PER_NODE_GROUP\fR
ExtraRowGciBits: 0
ExtraRowAuthorBits: 0
TableStatus: Retrieved
\fITable options: readbackup, fullyreplicated\fR
HashMap: DEFAULT\-HASHMAP\-3840\-1
\-\- Attributes \-\-
id Int PRIMARY KEY DISTRIBUTION KEY AT=FIXED ST=MEMORY AUTO_INCR
name Varchar(20;latin1_swedish_ci) NOT NULL AT=SHORT_VAR ST=MEMORY DYNAMIC
length_mm Int NOT NULL AT=FIXED ST=MEMORY DYNAMIC
weight_gm Int NOT NULL AT=FIXED ST=MEMORY DYNAMIC
\-\- Indexes \-\-
PRIMARY KEY(id) \- UniqueHashIndex
PRIMARY(id) \- OrderedIndex
uk(name) \- OrderedIndex
uk$unique(name) \- UniqueHashIndex
\-\- Per partition info \-\-
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space
NDBT_ProgramExit: 0 \- OK
.fi
.if n \{\
.RE
.\}
.PP
For more information about these table properties, see
Section\ \&13.1.20.11, \(lqSetting NDB_TABLE Options\(rq\&.
.PP
The
Extent_space
and
Free extent_space
columns are applicable only to
NDB
tables having columns on disk; for tables having only in\-memory columns, these columns always contain the value
0\&.
.PP
To illustrate their use, we modify the previous example\&. First, we must create the necessary Disk Data objects, as shown here:
.sp
.if n \{\
.RS 4
.\}
.nf
CREATE LOGFILE GROUP lg_1
ADD UNDOFILE \*(Aqundo_1\&.log\*(Aq
INITIAL_SIZE 16M
UNDO_BUFFER_SIZE 2M
ENGINE NDB;
ALTER LOGFILE GROUP lg_1
ADD UNDOFILE \*(Aqundo_2\&.log\*(Aq
INITIAL_SIZE 12M
ENGINE NDB;
CREATE TABLESPACE ts_1
ADD DATAFILE \*(Aqdata_1\&.dat\*(Aq
USE LOGFILE GROUP lg_1
INITIAL_SIZE 32M
ENGINE NDB;
ALTER TABLESPACE ts_1
ADD DATAFILE \*(Aqdata_2\&.dat\*(Aq
INITIAL_SIZE 48M
ENGINE NDB;
.fi
.if n \{\
.RE
.\}
.PP
(For more information on the statements just shown and the objects created by them, see
Section\ \&22.5.13.1, \(lqNDB Cluster Disk Data Objects\(rq, as well as
Section\ \&13.1.16, \(lqCREATE LOGFILE GROUP Syntax\(rq, and
Section\ \&13.1.21, \(lqCREATE TABLESPACE Syntax\(rq\&.)
.PP
Now we can create and populate a version of the
fish
table that stores 2 of its columns on disk (deleting the previous version of the table first, if it already exists):
.sp
.if n \{\
.RS 4
.\}
.nf
CREATE TABLE fish (
id INT(11) NOT NULL AUTO_INCREMENT,
name VARCHAR(20) NOT NULL,
length_mm INT(11) NOT NULL,
weight_gm INT(11) NOT NULL,
PRIMARY KEY pk (id),
UNIQUE KEY uk (name)
) TABLESPACE ts_1 STORAGE DISK
ENGINE=NDB;
INSERT INTO fish VALUES
(NULL, \*(Aqguppy\*(Aq, 35, 2), (NULL, \*(Aqtuna\*(Aq, 2500, 150000),
(NULL, \*(Aqshark\*(Aq, 3000, 110000), (NULL, \*(Aqmanta ray\*(Aq, 1500, 50000),
(NULL, \*(Aqgrouper\*(Aq, 900, 125000), (NULL ,\*(Aqpuffer\*(Aq, 250, 2500);
.fi
.if n \{\
.RE
.\}
.PP
When run against this version of the table,
\fBndb_desc\fR
displays the following output:
.sp
.if n \{\
.RS 4
.\}
.nf
shell> \fB\&./ndb_desc \-c localhost fish \-d test \-p\fR
\-\- fish \-\-
Version: 1
Fragment type: HashMapPartition
K Value: 6
Min load factor: 78
Max load factor: 80
Temporary table: no
Number of attributes: 4
Number of primary keys: 1
Length of frm data: 346
Max Rows: 0
Row Checksum: 1
Row GCI: 1
SingleUserMode: 0
ForceVarPart: 1
PartitionCount: 2
FragmentCount: 2
FragmentCountType: ONE_PER_LDM_PER_NODE
ExtraRowGciBits: 0
ExtraRowAuthorBits: 0
TableStatus: Retrieved
Table options:
HashMap: DEFAULT\-HASHMAP\-3840\-2
\-\- Attributes \-\-
id Int PRIMARY KEY DISTRIBUTION KEY AT=FIXED ST=MEMORY AUTO_INCR
name Varchar(20;latin1_swedish_ci) NOT NULL AT=SHORT_VAR ST=MEMORY
length_mm Int NOT NULL AT=FIXED ST=DISK
weight_gm Int NOT NULL AT=FIXED ST=DISK
\-\- Indexes \-\-
PRIMARY KEY(id) \- UniqueHashIndex
PRIMARY(id) \- OrderedIndex
uk(name) \- OrderedIndex
uk$unique(name) \- UniqueHashIndex
\-\- Per partition info \-\-
Partition Row count Commit count Frag fixed memory Frag varsized memory Extent_space Free extent_space
0 2 2 32768 32768 1048576 1044440
1 4 4 32768 32768 1048576 1044400
NDBT_ProgramExit: 0 \- OK
.fi
.if n \{\
.RE
.\}
.PP
This means that 1048576 bytes are allocated from the tablespace for this table on each partition, of which 1044440 bytes remain free for additional storage\&. In other words, 1048576 \- 1044440 = 4136 bytes per partition is currently being used to store the data from this table\*(Aqs disk\-based columns\&. The number of bytes shown as
Free extent_space
is available for storing on\-disk column data from the
fish
table only; for this reason, it is not visible when selecting from the
INFORMATION_SCHEMA\&.FILES
table\&.
.PP
For fully replicated tables,
\fBndb_desc\fR
shows only the nodes holding primary partition fragment replicas; nodes with copy fragment replicas (only) are ignored\&. Beginning with NDB 7\&.5\&.4, you can obtain such information, using the
\fBmysql\fR
client, from the
table_distribution_status,
table_fragments,
table_info, and
table_replicas
tables in the
ndbinfo
database\&.
.PP
The following table includes options that are specific to
\fBndb_desc\fR\&. Additional descriptions follow the table\&. For options common to most NDB Cluster programs (including
\fBndb_desc\fR), see
Options Common to NDB Cluster Programs(1)\&.
.sp
.it 1 an-trap
.nr an-no-space-flag 1
.nr an-break-flag 1
.br
.B Table\ \&22.332.\ \&Command\-line options for the ndb_desc program
.TS
allbox tab(:);
lB lB lB.
T{
Format
T}:T{
Description
T}:T{
Added, Deprecated, or Removed
T}
.T&
l l l
l l l
l l l
l l l
l l l
l l l
l l l.
T{
.PP
--blob-info,
.PP
-b
T}:T{
Include partition information for BLOB tables in output. Requires that
the -p option also be used
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--database=dbname,
.PP
-d
T}:T{
Name of database containing table
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--extra-node-info,
.PP
-n
T}:T{
Include partition-to-data-node mappings in output. Requires that the -p
option also be used
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--extra-partition-info,
.PP
-p
T}:T{
Display information about partitions
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--retries=#,
.PP
-r
T}:T{
Number of times to retry the connection (once per second)
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--table=tbl_name,
.PP
-t
T}:T{
Specify the table in which to find an index. When this option is used,
-p and -n have no effect and are ignored.
T}:T{
.PP
All NDB 8.0 releases
T}
T{
.PP
--unqualified,
.PP
-u
T}:T{
Use unqualified table names
T}:T{
.PP
All NDB 8.0 releases
T}
.TE
.sp 1
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-blob\-info\fR,
\fB\-b\fR
.sp
Include information about subordinate
BLOB
and
TEXT
columns\&.
.sp
Use of this option also requires the use of the
\fB\-\-extra\-partition\-info\fR
(\fB\-p\fR) option\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-database=\fR\fB\fIdb_name\fR\fR,
\fB\-d\fR
.sp
Specify the database in which the table should be found\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-extra\-node\-info\fR,
\fB\-n\fR
.sp
Include information about the mappings between table partitions and the data nodes upon which they reside\&. This information can be useful for verifying distribution awareness mechanisms and supporting more efficient application access to the data stored in NDB Cluster\&.
.sp
Use of this option also requires the use of the
\fB\-\-extra\-partition\-info\fR
(\fB\-p\fR) option\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-extra\-partition\-info\fR,
\fB\-p\fR
.sp
Print additional information about the table\*(Aqs partitions\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-retries=\fR\fB\fI#\fR\fR,
\fB\-r\fR
.sp
Try to connect this many times before giving up\&. One connect attempt is made per second\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-table=\fR\fB\fItbl_name\fR\fR,
\fB\-t\fR
.sp
Specify the table in which to look for an index\&.
.RE
.sp
.RS 4
.ie n \{\
\h'-04'\(bu\h'+03'\c
.\}
.el \{\
.sp -1
.IP \(bu 2.3
.\}
\fB\-\-unqualified\fR,
\fB\-u\fR
.sp
Use unqualified table names\&.
.RE
.PP
In NDB 7\&.5\&.3 and later, table indexes listed in the output are ordered by ID\&. Previously, this was not deterministic and could vary between platforms\&. (Bug #81763, Bug #23547742)
.SH "COPYRIGHT"
.br
.PP
Copyright \(co 1997, 2019, Oracle and/or its affiliates. All rights reserved.
.PP
This documentation is free software; you can redistribute it and/or modify it only under the terms of the GNU General Public License as published by the Free Software Foundation; version 2 of the License.
.PP
This documentation is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
.PP
You should have received a copy of the GNU General Public License along with the program; if not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA or see http://www.gnu.org/licenses/.
.sp
.SH "NOTES"
.IP " 1." 4
NDB Schema Object Versions
.RS 4
\%https://dev.mysql.com/doc/ndb-internals/en/ndb-internals-schema-object-versions.html
.RE
.SH "SEE ALSO"
For more information, please refer to the MySQL Reference Manual,
which may already be installed locally and which is also available
online at http://dev.mysql.com/doc/.
.SH AUTHOR
Oracle Corporation (http://dev.mysql.com/).