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# This is the test for Information Schema System Table View
# that displays the InnoDB system table content through
# information schema tables.
--source include/have_innodb.inc
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_INDEXES;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_COLUMNS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FIELDS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS;
# Create a foreign key constraint, and verify the information
# in INFORMATION_SCHEMA.INNODB_SYS_FOREIGN and
# INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)) ENGINE=INNODB;
CREATE TABLE child (id INT, parent_id INT,
INDEX par_ind (parent_id),
CONSTRAINT constraint_test
FOREIGN KEY (parent_id) REFERENCES parent(id)
ON DELETE CASCADE) ENGINE=INNODB;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS;
# Insert a row in the table "parent", and see whether that reflected in
# INNODB_SYS_TABLESTATS
INSERT INTO parent VALUES(1);
SELECT name, num_rows, mysql_handles_opened
FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS
WHERE name LIKE "%parent";
SELECT NAME, FLAG, N_COLS, SPACE FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES;
SELECT name, n_fields
from INFORMATION_SCHEMA.INNODB_SYS_INDEXES
WHERE table_id In (SELECT table_id from
INFORMATION_SCHEMA.INNODB_SYS_TABLES
WHERE name LIKE "%parent%");
SELECT name, n_fields
from INFORMATION_SCHEMA.INNODB_SYS_INDEXES
WHERE table_id In (SELECT table_id from
INFORMATION_SCHEMA.INNODB_SYS_TABLES
WHERE name LIKE "%child%");
SELECT name, pos, mtype, len
from INFORMATION_SCHEMA.INNODB_SYS_COLUMNS
WHERE table_id In (SELECT table_id from
INFORMATION_SCHEMA.INNODB_SYS_TABLES
WHERE name LIKE "%child%");
DROP TABLE child;
DROP TABLE parent;
# Create table with 2 columns in the foreign key constraint
CREATE TABLE parent (id INT NOT NULL, newid INT NOT NULL,
PRIMARY KEY (id, newid)) ENGINE=INNODB;
CREATE TABLE child (id INT, parent_id INT,
INDEX par_ind (parent_id),
CONSTRAINT constraint_test
FOREIGN KEY (id, parent_id) REFERENCES parent(id, newid)
ON DELETE CASCADE) ENGINE=INNODB;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_FOREIGN_COLS;
INSERT INTO parent VALUES(1, 9);
# Nested query will open the table handle twice
SELECT * FROM parent WHERE id IN (SELECT id FROM parent);
SELECT name, num_rows, mysql_handles_opened
FROM INFORMATION_SCHEMA.INNODB_SYS_TABLESTATS
WHERE name LIKE "%parent";
DROP TABLE child;
DROP TABLE parent;
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