MySQL Tutorial/Data Dictionary/INFORMATION SCHEMA — различия между версиями

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Версия 13:44, 26 мая 2010

The INFORMATION_SCHEMA.CHARACTER_SETS Table

The CHARACTER_SETS table provides information about available character sets.

The following statements are equivalent:



mysql> desc INFORMATION_SCHEMA.CHARACTER_SETS;
+----------------------+-------------+------+-----+---------+-------+
| Field                | Type        | Null | Key | Default | Extra |
+----------------------+-------------+------+-----+---------+-------+
| CHARACTER_SET_NAME   | varchar(64) | NO   |     |         |       |
| DEFAULT_COLLATE_NAME | varchar(64) | NO   |     |         |       |
| DESCRIPTION          | varchar(60) | NO   |     |         |       |
| MAXLEN               | bigint(3)   | NO   |     | 0       |       |
+----------------------+-------------+------+-----+---------+-------+
4 rows in set (0.02 sec)
mysql>
mysql> SELECT * FROM INFORMATION_SCHEMA.CHARACTER_SETS;
+--------------------+----------------------+-----------------------------+--------+
| CHARACTER_SET_NAME | DEFAULT_COLLATE_NAME | DESCRIPTION                 | MAXLEN |
+--------------------+----------------------+-----------------------------+--------+
| big5               | big5_chinese_ci      | Big5 Traditional Chinese    |      2 |
| dec8               | dec8_swedish_ci      | DEC West European           |      1 |
| cp850              | cp850_general_ci     | DOS West European           |      1 |
| hp8                | hp8_english_ci       | HP West European            |      1 |
| koi8r              | koi8r_general_ci     | KOI8-R Relcom Russian       |      1 |
| latin1             | latin1_swedish_ci    | cp1252 West European        |      1 |
| latin2             | latin2_general_ci    | ISO 8859-2 Central European |      1 |
| swe7               | swe7_swedish_ci      | 7bit Swedish                |      1 |
| ascii              | ascii_general_ci     | US ASCII                    |      1 |
| ujis               | ujis_japanese_ci     | EUC-JP Japanese             |      3 |
| sjis               | sjis_japanese_ci     | Shift-JIS Japanese          |      2 |
| hebrew             | hebrew_general_ci    | ISO 8859-8 Hebrew           |      1 |
| tis620             | tis620_thai_ci       | TIS620 Thai                 |      1 |
| euckr              | euckr_korean_ci      | EUC-KR Korean               |      2 |
| koi8u              | koi8u_general_ci     | KOI8-U Ukrainian            |      1 |
| gb2312             | gb2312_chinese_ci    | GB2312 Simplified Chinese   |      2 |
| greek              | greek_general_ci     | ISO 8859-7 Greek            |      1 |
| cp1250             | cp1250_general_ci    | Windows Central European    |      1 |
| gbk                | gbk_chinese_ci       | GBK Simplified Chinese      |      2 |
| latin5             | latin5_turkish_ci    | ISO 8859-9 Turkish          |      1 |
| armscii8           | armscii8_general_ci  | ARMSCII-8 Armenian          |      1 |
| utf8               | utf8_general_ci      | UTF-8 Unicode               |      3 |
| ucs2               | ucs2_general_ci      | UCS-2 Unicode               |      2 |
| cp866              | cp866_general_ci     | DOS Russian                 |      1 |
| keybcs2            | keybcs2_general_ci   | DOS Kamenicky Czech-Slovak  |      1 |
| macce              | macce_general_ci     | Mac Central European        |      1 |
| macroman           | macroman_general_ci  | Mac West European           |      1 |
| cp852              | cp852_general_ci     | DOS Central European        |      1 |
| latin7             | latin7_general_ci    | ISO 8859-13 Baltic          |      1 |
| cp1251             | cp1251_general_ci    | Windows Cyrillic            |      1 |
| cp1256             | cp1256_general_ci    | Windows Arabic              |      1 |
| cp1257             | cp1257_general_ci    | Windows Baltic              |      1 |
| binary             | binary               | Binary pseudo charset       |      1 |
| geostd8            | geostd8_general_ci   | GEOSTD8 Georgian            |      1 |
| cp932              | cp932_japanese_ci    | SJIS for Windows Japanese   |      2 |
| eucjpms            | eucjpms_japanese_ci  | UJIS for Windows Japanese   |      3 |
+--------------------+----------------------+-----------------------------+--------+
36 rows in set (0.02 sec)
mysql>
mysql> SHOW CHARACTER SET;
+----------+-----------------------------+---------------------+--------+
| Charset  | Description                 | Default collation   | Maxlen |
+----------+-----------------------------+---------------------+--------+
| big5     | Big5 Traditional Chinese    | big5_chinese_ci     |      2 |
| dec8     | DEC West European           | dec8_swedish_ci     |      1 |
| cp850    | DOS West European           | cp850_general_ci    |      1 |
| hp8      | HP West European            | hp8_english_ci      |      1 |
| koi8r    | KOI8-R Relcom Russian       | koi8r_general_ci    |      1 |
| latin1   | cp1252 West European        | latin1_swedish_ci   |      1 |
| latin2   | ISO 8859-2 Central European | latin2_general_ci   |      1 |
| swe7     | 7bit Swedish                | swe7_swedish_ci     |      1 |
| ascii    | US ASCII                    | ascii_general_ci    |      1 |
| ujis     | EUC-JP Japanese             | ujis_japanese_ci    |      3 |
| sjis     | Shift-JIS Japanese          | sjis_japanese_ci    |      2 |
| hebrew   | ISO 8859-8 Hebrew           | hebrew_general_ci   |      1 |
| tis620   | TIS620 Thai                 | tis620_thai_ci      |      1 |
| euckr    | EUC-KR Korean               | euckr_korean_ci     |      2 |
| koi8u    | KOI8-U Ukrainian            | koi8u_general_ci    |      1 |
| gb2312   | GB2312 Simplified Chinese   | gb2312_chinese_ci   |      2 |
| greek    | ISO 8859-7 Greek            | greek_general_ci    |      1 |
| cp1250   | Windows Central European    | cp1250_general_ci   |      1 |
| gbk      | GBK Simplified Chinese      | gbk_chinese_ci      |      2 |
| latin5   | ISO 8859-9 Turkish          | latin5_turkish_ci   |      1 |
| armscii8 | ARMSCII-8 Armenian          | armscii8_general_ci |      1 |
| utf8     | UTF-8 Unicode               | utf8_general_ci     |      3 |
| ucs2     | UCS-2 Unicode               | ucs2_general_ci     |      2 |
| cp866    | DOS Russian                 | cp866_general_ci    |      1 |
| keybcs2  | DOS Kamenicky Czech-Slovak  | keybcs2_general_ci  |      1 |
| macce    | Mac Central European        | macce_general_ci    |      1 |
| macroman | Mac West European           | macroman_general_ci |      1 |
| cp852    | DOS Central European        | cp852_general_ci    |      1 |
| latin7   | ISO 8859-13 Baltic          | latin7_general_ci   |      1 |
| cp1251   | Windows Cyrillic            | cp1251_general_ci   |      1 |
| cp1256   | Windows Arabic              | cp1256_general_ci   |      1 |
| cp1257   | Windows Baltic              | cp1257_general_ci   |      1 |
| binary   | Binary pseudo charset       | binary              |      1 |
| geostd8  | GEOSTD8 Georgian            | geostd8_general_ci  |      1 |
| cp932    | SJIS for Windows Japanese   | cp932_japanese_ci   |      2 |
| eucjpms  | UJIS for Windows Japanese   | eucjpms_japanese_ci |      3 |
+----------+-----------------------------+---------------------+--------+
36 rows in set (0.00 sec)


The INFORMATION_SCHEMA.COLLATION_CHARACTER_SET_APPLICABILITY Table

The COLLATION_CHARACTER_SET_APPLICABILITY table indicates what character set is applicable for what collation.

The columns are equivalent to the first two display fields that we get from SHOW COLLATION.



mysql> desc INFORMATION_SCHEMA.COLLATION_CHARACTER_SET_APPLICABILITY;
+--------------------+-------------+------+-----+---------+-------+
| Field              | Type        | Null | Key | Default | Extra |
+--------------------+-------------+------+-----+---------+-------+
| COLLATION_NAME     | varchar(64) | NO   |     |         |       |
| CHARACTER_SET_NAME | varchar(64) | NO   |     |         |       |
+--------------------+-------------+------+-----+---------+-------+
2 rows in set (0.00 sec)


The INFORMATION_SCHEMA.COLLATIONS Table

The COLLATIONS table provides information about collations for each character set.



mysql>
mysql> desc INFORMATION_SCHEMA.COLLATIONS;
+--------------------+-------------+------+-----+---------+-------+
| Field              | Type        | Null | Key | Default | Extra |
+--------------------+-------------+------+-----+---------+-------+
| COLLATION_NAME     | varchar(64) | NO   |     |         |       |
| CHARACTER_SET_NAME | varchar(64) | NO   |     |         |       |
| ID                 | bigint(11)  | NO   |     | 0       |       |
| IS_DEFAULT         | varchar(3)  | NO   |     |         |       |
| IS_COMPILED        | varchar(3)  | NO   |     |         |       |
| SORTLEN            | bigint(3)   | NO   |     | 0       |       |
+--------------------+-------------+------+-----+---------+-------+
6 rows in set (0.00 sec)


The INFORMATION_SCHEMA.COLUMN_PRIVILEGES Table

The COLUMN_PRIVILEGES table provides information about column privileges.

PRIVILEGE_TYPE can contain one (and only one) of these values: SELECT, INSERT, UPDATE, REFERENCES.

This information comes from the mysql.columns_priv grant table.

25. 8. INFORMATION_SCHEMA 25. 8. 1. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMADatabase.htm">The INFORMATION_SCHEMA Database</a> 25. 8. 2. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASCHEMATATable.htm">The INFORMATION_SCHEMA.SCHEMATA Table</a> 25. 8. 3. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATABLESTable.htm">The INFORMATION_SCHEMA.TABLES Table</a> 25. 8. 4. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLUMNSTable.htm">The INFORMATION_SCHEMA.COLUMNS Table</a> 25. 8. 5. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASTATISTICSTable.htm">The INFORMATION_SCHEMA.STATISTICS Table</a> 25. 8. 6. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAUSERPRIVILEGESTable.htm">The INFORMATION_SCHEMA.USER_PRIVILEGES Table</a> 25. 8. 7. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASCHEMAPRIVILEGESTable.htm">The INFORMATION_SCHEMA.SCHEMA_PRIVILEGES Table</a> 25. 8. 8. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATABLEPRIVILEGESTable.htm">The INFORMATION_SCHEMA.TABLE_PRIVILEGES Table</a> 25. 8. 9. The INFORMATION_SCHEMA.COLUMN_PRIVILEGES Table 25. 8. 10. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACHARACTERSETSTable.htm">The INFORMATION_SCHEMA.CHARACTER_SETS Table</a> 25. 8. 11. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLLATIONSTable.htm">The INFORMATION_SCHEMA.COLLATIONS Table</a> 25. 8. 12. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLLATIONCHARACTERSETAPPLICABILITYTable.htm">The INFORMATION_SCHEMA.COLLATION_CHARACTER_SET_APPLICABILITY Table</a> 25. 8. 13. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATABLECONSTRAINTSTable.htm">The INFORMATION_SCHEMA.TABLE_CONSTRAINTS Table</a> 25. 8. 14. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAKEYCOLUMNUSAGETable.htm">The INFORMATION_SCHEMA KEY_COLUMN_USAGE Table</a> 25. 8. 15. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAROUTINESTable.htm">The INFORMATION_SCHEMA ROUTINES Table</a> 25. 8. 16. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAVIEWSTable.htm">The INFORMATION_SCHEMA.VIEWS Table</a> 25. 8. 17. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATRIGGERSTable.htm">The INFORMATION_SCHEMA.TRIGGERS Table</a> 25. 8. 18. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAPROFILINGTable.htm">The INFORMATION_SCHEMA.PROFILING Table</a>

The INFORMATION_SCHEMA.COLUMNS Table

The COLUMNS table provides information about columns in tables.



mysql> desc INFORMATION_SCHEMA.COLUMNS;
+--------------------------+--------------+------+-----+---------+-------+
| Field                    | Type         | Null | Key | Default | Extra |
+--------------------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG            | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA             | varchar(64)  | NO   |     |         |       |
| TABLE_NAME               | varchar(64)  | NO   |     |         |       |
| COLUMN_NAME              | varchar(64)  | NO   |     |         |       |
| ORDINAL_POSITION         | bigint(21)   | NO   |     | 0       |       |
| COLUMN_DEFAULT           | longtext     | YES  |     | NULL    |       |
| IS_NULLABLE              | varchar(3)   | NO   |     |         |       |
| DATA_TYPE                | varchar(64)  | NO   |     |         |       |
| CHARACTER_MAXIMUM_LENGTH | bigint(21)   | YES  |     | NULL    |       |
| CHARACTER_OCTET_LENGTH   | bigint(21)   | YES  |     | NULL    |       |
| NUMERIC_PRECISION        | bigint(21)   | YES  |     | NULL    |       |
| NUMERIC_SCALE            | bigint(21)   | YES  |     | NULL    |       |
| CHARACTER_SET_NAME       | varchar(64)  | YES  |     | NULL    |       |
| COLLATION_NAME           | varchar(64)  | YES  |     | NULL    |       |
| COLUMN_TYPE              | longtext     | NO   |     |         |       |
| COLUMN_KEY               | varchar(3)   | NO   |     |         |       |
| EXTRA                    | varchar(20)  | NO   |     |         |       |
| PRIVILEGES               | varchar(80)  | NO   |     |         |       |
| COLUMN_COMMENT           | varchar(255) | NO   |     |         |       |
+--------------------------+--------------+------+-----+---------+-------+
19 rows in set (0.02 sec)


The INFORMATION_SCHEMA Database

INFORMATION_SCHEMA provides access to database metadata.

Metadata is data about the data.

For example, the name of a database or table, the data type of a column, or access privileges.

INFORMATION_SCHEMA is the information database.

Inside INFORMATION_SCHEMA there are several read-only tables.

They are actually views.

It is possible to select INFORMATION_SCHEMA as the default database with a USE statement.

SELECT ... FROM INFORMATION_SCHEMA statement is a more consistent way to provide access to the information provided by the various SHOW statements that.



mysql> CREATE TABLE Employee(
    ->     id            int,
    ->     first_name    VARCHAR(15),
    ->     last_name     VARCHAR(15),
    ->     start_date    DATE,
    ->     end_date      DATE,
    ->     salary        FLOAT(8,2),
    ->     city          VARCHAR(10),
    ->     description   VARCHAR(15)
    -> );
Query OK, 0 rows affected (0.01 sec)
mysql>
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->              values (1,"Jason",    "Martin",  "19960725",  "20060725", 1234.56, "Toronto",  "Programmer");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(2,"Alison",   "Mathews",  "19760321", "19860221", 6661.78, "Vancouver","Tester");
Query OK, 1 row affected (0.01 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(3,"James",    "Smith",    "19781212", "19900315", 6544.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(4,"Celia",    "Rice",     "19821024", "19990421", 2344.78, "Vancouver","Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(5,"Robert",   "Black",    "19840115", "19980808", 2334.78, "Vancouver","Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(6,"Linda",    "Green",    "19870730", "19960104", 4322.78,"New York",  "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(7,"David",    "Larry",    "19901231", "19980212", 7897.78,"New York",  "Manager");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> insert into Employee(id,first_name, last_name, start_date, end_Date,   salary,  City,       Description)
    ->               values(8,"James",    "Cat",     "19960917",  "20020415", 1232.78,"Vancouver", "Tester");
Query OK, 1 row affected (0.00 sec)
mysql>
mysql> select * from Employee;
+------+------------+-----------+------------+------------+---------+-----------+-------------+
| id   | first_name | last_name | start_date | end_date   | salary  | city      | description |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
|    1 | Jason      | Martin    | 1996-07-25 | 2006-07-25 | 1234.56 | Toronto   | Programmer  |
|    2 | Alison     | Mathews   | 1976-03-21 | 1986-02-21 | 6661.78 | Vancouver | Tester      |
|    3 | James      | Smith     | 1978-12-12 | 1990-03-15 | 6544.78 | Vancouver | Tester      |
|    4 | Celia      | Rice      | 1982-10-24 | 1999-04-21 | 2344.78 | Vancouver | Manager     |
|    5 | Robert     | Black     | 1984-01-15 | 1998-08-08 | 2334.78 | Vancouver | Tester      |
|    6 | Linda      | Green     | 1987-07-30 | 1996-01-04 | 4322.78 | New York  | Tester      |
|    7 | David      | Larry     | 1990-12-31 | 1998-02-12 | 7897.78 | New York  | Manager     |
|    8 | James      | Cat       | 1996-09-17 | 2002-04-15 | 1232.78 | Vancouver | Tester      |
+------+------------+-----------+------------+------------+---------+-----------+-------------+
8 rows in set (0.00 sec)
mysql>
mysql>
mysql>
mysql> SELECT table_name, table_type, engine
    -> FROM information_schema.tables;
+---------------------------------------+-------------+--------+
| table_name                            | table_type  | engine |
+---------------------------------------+-------------+--------+
| CHARACTER_SETS                        | SYSTEM VIEW | MEMORY |
| COLLATIONS                            | SYSTEM VIEW | MEMORY |
| COLLATION_CHARACTER_SET_APPLICABILITY | SYSTEM VIEW | MEMORY |
| COLUMNS                               | SYSTEM VIEW | MyISAM |
| COLUMN_PRIVILEGES                     | SYSTEM VIEW | MEMORY |
| KEY_COLUMN_USAGE                      | SYSTEM VIEW | MEMORY |
| PROFILING                             | SYSTEM VIEW | MEMORY |
| ROUTINES                              | SYSTEM VIEW | MyISAM |
| SCHEMATA                              | SYSTEM VIEW | MEMORY |
| SCHEMA_PRIVILEGES                     | SYSTEM VIEW | MEMORY |
| STATISTICS                            | SYSTEM VIEW | MEMORY |
| TABLES                                | SYSTEM VIEW | MEMORY |
| TABLE_CONSTRAINTS                     | SYSTEM VIEW | MEMORY |
| TABLE_PRIVILEGES                      | SYSTEM VIEW | MEMORY |
| TRIGGERS                              | SYSTEM VIEW | MyISAM |
| USER_PRIVILEGES                       | SYSTEM VIEW | MEMORY |
| VIEWS                                 | SYSTEM VIEW | MyISAM |
| columns_priv                          | BASE TABLE  | MyISAM |
| db                                    | BASE TABLE  | MyISAM |
| func                                  | BASE TABLE  | MyISAM |
| help_category                         | BASE TABLE  | MyISAM |
| help_keyword                          | BASE TABLE  | MyISAM |
| help_relation                         | BASE TABLE  | MyISAM |
| help_topic                            | BASE TABLE  | MyISAM |
| host                                  | BASE TABLE  | MyISAM |
| proc                                  | BASE TABLE  | MyISAM |
| procs_priv                            | BASE TABLE  | MyISAM |
| tables_priv                           | BASE TABLE  | MyISAM |
| time_zone                             | BASE TABLE  | MyISAM |
| time_zone_leap_second                 | BASE TABLE  | MyISAM |
| time_zone_name                        | BASE TABLE  | MyISAM |
| time_zone_transition                  | BASE TABLE  | MyISAM |
| time_zone_transition_type             | BASE TABLE  | MyISAM |
| user                                  | BASE TABLE  | MyISAM |
| employee                              | BASE TABLE  | MyISAM |
| v                                     | VIEW        | NULL   |
+---------------------------------------+-------------+--------+
36 rows in set (0.01 sec)
mysql>
mysql>
mysql>
mysql>
mysql>
mysql> drop table Employee;
Query OK, 0 rows affected (0.00 sec)
mysql>
mysql>


The INFORMATION_SCHEMA KEY_COLUMN_USAGE Table

The KEY_COLUMN_USAGE table describes which key columns have constraints.



mysql>
mysql>
mysql> desc  INFORMATION_SCHEMA.KEY_COLUMN_USAGE;
+-------------------------------+--------------+------+-----+---------+-------+
| Field                         | Type         | Null | Key | Default | Extra |
+-------------------------------+--------------+------+-----+---------+-------+
| CONSTRAINT_CATALOG            | varchar(512) | YES  |     | NULL    |       |
| CONSTRAINT_SCHEMA             | varchar(64)  | NO   |     |         |       |
| CONSTRAINT_NAME               | varchar(64)  | NO   |     |         |       |
| TABLE_CATALOG                 | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA                  | varchar(64)  | NO   |     |         |       |
| TABLE_NAME                    | varchar(64)  | NO   |     |         |       |
| COLUMN_NAME                   | varchar(64)  | NO   |     |         |       |
| ORDINAL_POSITION              | bigint(10)   | NO   |     | 0       |       |
| POSITION_IN_UNIQUE_CONSTRAINT | bigint(10)   | YES  |     | NULL    |       |
| REFERENCED_TABLE_SCHEMA       | varchar(64)  | YES  |     | NULL    |       |
| REFERENCED_TABLE_NAME         | varchar(64)  | YES  |     | NULL    |       |
| REFERENCED_COLUMN_NAME        | varchar(64)  | YES  |     | NULL    |       |
+-------------------------------+--------------+------+-----+---------+-------+
12 rows in set (0.00 sec)


The INFORMATION_SCHEMA.PROFILING Table

mysql> desc INFORMATION_SCHEMA.PROFILING;
+---------------------+-------------+------+-----+---------+-------+
| Field               | Type        | Null | Key | Default | Extra |
+---------------------+-------------+------+-----+---------+-------+
| QUERY_ID            | bigint(20)  | NO   |     | 0       |       |
| SEQ                 | bigint(20)  | NO   |     | 0       |       |
| STATE               | varchar(30) | NO   |     |         |       |
| DURATION            | double      | NO   |     | 0       |       |
| CPU_USER            | double      | YES  |     | NULL    |       |
| CPU_SYSTEM          | double      | YES  |     | NULL    |       |
| CONTEXT_VOLUNTARY   | bigint(20)  | YES  |     | NULL    |       |
| CONTEXT_INVOLUNTARY | bigint(20)  | YES  |     | NULL    |       |
| BLOCK_OPS_IN        | bigint(20)  | YES  |     | NULL    |       |
| BLOCK_OPS_OUT       | bigint(20)  | YES  |     | NULL    |       |
| MESSAGES_SENT       | bigint(20)  | YES  |     | NULL    |       |
| MESSAGES_RECEIVED   | bigint(20)  | YES  |     | NULL    |       |
| PAGE_FAULTS_MAJOR   | bigint(20)  | YES  |     | NULL    |       |
| PAGE_FAULTS_MINOR   | bigint(20)  | YES  |     | NULL    |       |
| SWAPS               | bigint(20)  | YES  |     | NULL    |       |
| SOURCE_FUNCTION     | varchar(30) | YES  |     | NULL    |       |
| SOURCE_FILE         | varchar(20) | YES  |     | NULL    |       |
| SOURCE_LINE         | bigint(20)  | YES  |     | NULL    |       |
+---------------------+-------------+------+-----+---------+-------+
18 rows in set (0.03 sec)


The INFORMATION_SCHEMA ROUTINES Table

The ROUTINES table provides information about procedures and functions.

The column named "mysql.proc name" indicates the mysql.proc table column that corresponds to the INFORMATION_SCHEMA.ROUTINES table column, if any.



mysql> desc INFORMATION_SCHEMA.ROUTINES;
+--------------------+--------------+------+-----+---------------------+-------+
| Field              | Type         | Null | Key | Default             | Extra |
+--------------------+--------------+------+-----+---------------------+-------+
| SPECIFIC_NAME      | varchar(64)  | NO   |     |                     |       |
| ROUTINE_CATALOG    | varchar(512) | YES  |     | NULL                |       |
| ROUTINE_SCHEMA     | varchar(64)  | NO   |     |                     |       |
| ROUTINE_NAME       | varchar(64)  | NO   |     |                     |       |
| ROUTINE_TYPE       | varchar(9)   | NO   |     |                     |       |
| DTD_IDENTIFIER     | varchar(64)  | YES  |     | NULL                |       |
| ROUTINE_BODY       | varchar(8)   | NO   |     |                     |       |
| ROUTINE_DEFINITION | longtext     | YES  |     | NULL                |       |
| EXTERNAL_NAME      | varchar(64)  | YES  |     | NULL                |       |
| EXTERNAL_LANGUAGE  | varchar(64)  | YES  |     | NULL                |       |
| PARAMETER_STYLE    | varchar(8)   | NO   |     |                     |       |
| IS_DETERMINISTIC   | varchar(3)   | NO   |     |                     |       |
| SQL_DATA_ACCESS    | varchar(64)  | NO   |     |                     |       |
| SQL_PATH           | varchar(64)  | YES  |     | NULL                |       |
| SECURITY_TYPE      | varchar(7)   | NO   |     |                     |       |
| CREATED            | datetime     | NO   |     | 0000-00-00 00:00:00 |       |
| LAST_ALTERED       | datetime     | NO   |     | 0000-00-00 00:00:00 |       |
| SQL_MODE           | longtext     | NO   |     |                     |       |
| ROUTINE_COMMENT    | varchar(64)  | NO   |     |                     |       |
| DEFINER            | varchar(77)  | NO   |     |                     |       |
+--------------------+--------------+------+-----+---------------------+-------+
20 rows in set (0.02 sec)


The INFORMATION_SCHEMA.SCHEMA_PRIVILEGES Table

The SCHEMA_PRIVILEGES table provides information about schema (database) privileges.

This information comes from the mysql.db grant table.



mysql>
mysql> desc INFORMATION_SCHEMA.SCHEMA_PRIVILEGES;
+----------------+--------------+------+-----+---------+-------+
| Field          | Type         | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| GRANTEE        | varchar(81)  | NO   |     |         |       |
| TABLE_CATALOG  | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA   | varchar(64)  | NO   |     |         |       |
| PRIVILEGE_TYPE | varchar(64)  | NO   |     |         |       |
| IS_GRANTABLE   | varchar(3)   | NO   |     |         |       |
+----------------+--------------+------+-----+---------+-------+
5 rows in set (0.00 sec)


The INFORMATION_SCHEMA.SCHEMATA Table

A schema is a database, so the SCHEMATA table provides information about databases.



mysql> desc INFORMATION_SCHEMA.SCHEMATA;
+----------------------------+--------------+------+-----+---------+-------+
| Field                      | Type         | Null | Key | Default | Extra |
+----------------------------+--------------+------+-----+---------+-------+
| CATALOG_NAME               | varchar(512) | YES  |     | NULL    |       |
| SCHEMA_NAME                | varchar(64)  | NO   |     |         |       |
| DEFAULT_CHARACTER_SET_NAME | varchar(64)  | NO   |     |         |       |
| DEFAULT_COLLATION_NAME     | varchar(64)  | NO   |     |         |       |
| SQL_PATH                   | varchar(512) | YES  |     | NULL    |       |
+----------------------------+--------------+------+-----+---------+-------+
5 rows in set (0.00 sec)


The INFORMATION_SCHEMA.STATISTICS Table

The STATISTICS table provides information about table indexes.



mysql> desc INFORMATION_SCHEMA.STATISTICS;
+---------------+--------------+------+-----+---------+-------+
| Field         | Type         | Null | Key | Default | Extra |
+---------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA  | varchar(64)  | NO   |     |         |       |
| TABLE_NAME    | varchar(64)  | NO   |     |         |       |
| NON_UNIQUE    | bigint(1)    | NO   |     | 0       |       |
| INDEX_SCHEMA  | varchar(64)  | NO   |     |         |       |
| INDEX_NAME    | varchar(64)  | NO   |     |         |       |
| SEQ_IN_INDEX  | bigint(2)    | NO   |     | 0       |       |
| COLUMN_NAME   | varchar(64)  | NO   |     |         |       |
| COLLATION     | varchar(1)   | YES  |     | NULL    |       |
| CARDINALITY   | bigint(21)   | YES  |     | NULL    |       |
| SUB_PART      | bigint(3)    | YES  |     | NULL    |       |
| PACKED        | varchar(10)  | YES  |     | NULL    |       |
| NULLABLE      | varchar(3)   | NO   |     |         |       |
| INDEX_TYPE    | varchar(16)  | NO   |     |         |       |
| COMMENT       | varchar(16)  | YES  |     | NULL    |       |
+---------------+--------------+------+-----+---------+-------+
15 rows in set (0.02 sec)


The INFORMATION_SCHEMA.TABLE_CONSTRAINTS Table

The TABLE_CONSTRAINTS table describes which tables have constraints.

The CONSTRAINT_TYPE value can be UNIQUE, PRIMARY KEY, or FOREIGN KEY.

The CONSTRAINT_TYPE column can contain one of these values: UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK.

25. 8. INFORMATION_SCHEMA 25. 8. 1. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMADatabase.htm">The INFORMATION_SCHEMA Database</a> 25. 8. 2. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASCHEMATATable.htm">The INFORMATION_SCHEMA.SCHEMATA Table</a> 25. 8. 3. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATABLESTable.htm">The INFORMATION_SCHEMA.TABLES Table</a> 25. 8. 4. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLUMNSTable.htm">The INFORMATION_SCHEMA.COLUMNS Table</a> 25. 8. 5. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASTATISTICSTable.htm">The INFORMATION_SCHEMA.STATISTICS Table</a> 25. 8. 6. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAUSERPRIVILEGESTable.htm">The INFORMATION_SCHEMA.USER_PRIVILEGES Table</a> 25. 8. 7. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMASCHEMAPRIVILEGESTable.htm">The INFORMATION_SCHEMA.SCHEMA_PRIVILEGES Table</a> 25. 8. 8. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATABLEPRIVILEGESTable.htm">The INFORMATION_SCHEMA.TABLE_PRIVILEGES Table</a> 25. 8. 9. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLUMNPRIVILEGESTable.htm">The INFORMATION_SCHEMA.COLUMN_PRIVILEGES Table</a> 25. 8. 10. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACHARACTERSETSTable.htm">The INFORMATION_SCHEMA.CHARACTER_SETS Table</a> 25. 8. 11. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLLATIONSTable.htm">The INFORMATION_SCHEMA.COLLATIONS Table</a> 25. 8. 12. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMACOLLATIONCHARACTERSETAPPLICABILITYTable.htm">The INFORMATION_SCHEMA.COLLATION_CHARACTER_SET_APPLICABILITY Table</a> 25. 8. 13. The INFORMATION_SCHEMA.TABLE_CONSTRAINTS Table 25. 8. 14. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAKEYCOLUMNUSAGETable.htm">The INFORMATION_SCHEMA KEY_COLUMN_USAGE Table</a> 25. 8. 15. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAROUTINESTable.htm">The INFORMATION_SCHEMA ROUTINES Table</a> 25. 8. 16. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAVIEWSTable.htm">The INFORMATION_SCHEMA.VIEWS Table</a> 25. 8. 17. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMATRIGGERSTable.htm">The INFORMATION_SCHEMA.TRIGGERS Table</a> 25. 8. 18. <A href="/Tutorial/MySQL/0500__Data-Dictionary/TheINFORMATIONSCHEMAPROFILINGTable.htm">The INFORMATION_SCHEMA.PROFILING Table</a>

The INFORMATION_SCHEMA.TABLE_PRIVILEGES Table

The TABLE_PRIVILEGES table provides information about table privileges.

PRIVILEGE_TYPE can contain one (and only one) of these values: SELECT, INSERT, UPDATE, REFERENCES, ALTER, INDEX, DROP, CREATE VIEW.

This information comes from the mysql.tables_priv grant table.



mysql>
mysql> desc INFORMATION_SCHEMA.TABLE_PRIVILEGES;
+----------------+--------------+------+-----+---------+-------+
| Field          | Type         | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| GRANTEE        | varchar(81)  | NO   |     |         |       |
| TABLE_CATALOG  | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA   | varchar(64)  | NO   |     |         |       |
| TABLE_NAME     | varchar(64)  | NO   |     |         |       |
| PRIVILEGE_TYPE | varchar(64)  | NO   |     |         |       |
| IS_GRANTABLE   | varchar(3)   | NO   |     |         |       |
+----------------+--------------+------+-----+---------+-------+
6 rows in set (0.02 sec)


The INFORMATION_SCHEMA.TABLES Table

The TABLES table provides information about tables in databases.



mysql> desc INFORMATION_SCHEMA.TABLES;
+-----------------+--------------+------+-----+---------+-------+
| Field           | Type         | Null | Key | Default | Extra |
+-----------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG   | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA    | varchar(64)  | NO   |     |         |       |
| TABLE_NAME      | varchar(64)  | NO   |     |         |       |
| TABLE_TYPE      | varchar(64)  | NO   |     |         |       |
| ENGINE          | varchar(64)  | YES  |     | NULL    |       |
| VERSION         | bigint(21)   | YES  |     | NULL    |       |
| ROW_FORMAT      | varchar(10)  | YES  |     | NULL    |       |
| TABLE_ROWS      | bigint(21)   | YES  |     | NULL    |       |
| AVG_ROW_LENGTH  | bigint(21)   | YES  |     | NULL    |       |
| DATA_LENGTH     | bigint(21)   | YES  |     | NULL    |       |
| MAX_DATA_LENGTH | bigint(21)   | YES  |     | NULL    |       |
| INDEX_LENGTH    | bigint(21)   | YES  |     | NULL    |       |
| DATA_FREE       | bigint(21)   | YES  |     | NULL    |       |
| AUTO_INCREMENT  | bigint(21)   | YES  |     | NULL    |       |
| CREATE_TIME     | datetime     | YES  |     | NULL    |       |
| UPDATE_TIME     | datetime     | YES  |     | NULL    |       |
| CHECK_TIME      | datetime     | YES  |     | NULL    |       |
| TABLE_COLLATION | varchar(64)  | YES  |     | NULL    |       |
| CHECKSUM        | bigint(21)   | YES  |     | NULL    |       |
| CREATE_OPTIONS  | varchar(255) | YES  |     | NULL    |       |
| TABLE_COMMENT   | varchar(80)  | NO   |     |         |       |
+-----------------+--------------+------+-----+---------+-------+
21 rows in set (0.01 sec)


The INFORMATION_SCHEMA.TRIGGERS Table

The TRIGGERS table provides information about triggers.



mysql> desc INFORMATION_SCHEMA.TRIGGERS;
+----------------------------+--------------+------+-----+---------+-------+
| Field                      | Type         | Null | Key | Default | Extra |
+----------------------------+--------------+------+-----+---------+-------+
| TRIGGER_CATALOG            | varchar(512) | YES  |     | NULL    |       |
| TRIGGER_SCHEMA             | varchar(64)  | NO   |     |         |       |
| TRIGGER_NAME               | varchar(64)  | NO   |     |         |       |
| EVENT_MANIPULATION         | varchar(6)   | NO   |     |         |       |
| EVENT_OBJECT_CATALOG       | varchar(512) | YES  |     | NULL    |       |
| EVENT_OBJECT_SCHEMA        | varchar(64)  | NO   |     |         |       |
| EVENT_OBJECT_TABLE         | varchar(64)  | NO   |     |         |       |
| ACTION_ORDER               | bigint(4)    | NO   |     | 0       |       |
| ACTION_CONDITION           | longtext     | YES  |     | NULL    |       |
| ACTION_STATEMENT           | longtext     | NO   |     |         |       |
| ACTION_ORIENTATION         | varchar(9)   | NO   |     |         |       |
| ACTION_TIMING              | varchar(6)   | NO   |     |         |       |
| ACTION_REFERENCE_OLD_TABLE | varchar(64)  | YES  |     | NULL    |       |
| ACTION_REFERENCE_NEW_TABLE | varchar(64)  | YES  |     | NULL    |       |
| ACTION_REFERENCE_OLD_ROW   | varchar(3)   | NO   |     |         |       |
| ACTION_REFERENCE_NEW_ROW   | varchar(3)   | NO   |     |         |       |
| CREATED                    | datetime     | YES  |     | NULL    |       |
| SQL_MODE                   | longtext     | NO   |     |         |       |
| DEFINER                    | longtext     | NO   |     |         |       |
+----------------------------+--------------+------+-----+---------+-------+
19 rows in set (0.02 sec)


The INFORMATION_SCHEMA.USER_PRIVILEGES Table

mysql> desc INFORMATION_SCHEMA.USER_PRIVILEGES;
+----------------+--------------+------+-----+---------+-------+
| Field          | Type         | Null | Key | Default | Extra |
+----------------+--------------+------+-----+---------+-------+
| GRANTEE        | varchar(81)  | NO   |     |         |       |
| TABLE_CATALOG  | varchar(512) | YES  |     | NULL    |       |
| PRIVILEGE_TYPE | varchar(64)  | NO   |     |         |       |
| IS_GRANTABLE   | varchar(3)   | NO   |     |         |       |
+----------------+--------------+------+-----+---------+-------+
4 rows in set (0.02 sec)


The INFORMATION_SCHEMA.VIEWS Table

The VIEWS table provides information about views in databases. You must have the SHOW VIEW privilege to access this table.



mysql> desc INFORMATION_SCHEMA.VIEWS;
+-----------------+--------------+------+-----+---------+-------+
| Field           | Type         | Null | Key | Default | Extra |
+-----------------+--------------+------+-----+---------+-------+
| TABLE_CATALOG   | varchar(512) | YES  |     | NULL    |       |
| TABLE_SCHEMA    | varchar(64)  | NO   |     |         |       |
| TABLE_NAME      | varchar(64)  | NO   |     |         |       |
| VIEW_DEFINITION | longtext     | NO   |     |         |       |
| CHECK_OPTION    | varchar(8)   | NO   |     |         |       |
| IS_UPDATABLE    | varchar(3)   | NO   |     |         |       |
| DEFINER         | varchar(77)  | NO   |     |         |       |
| SECURITY_TYPE   | varchar(7)   | NO   |     |         |       |
+-----------------+--------------+------+-----+---------+-------+
8 rows in set (0.02 sec)