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CREATE TABLE t1(id INT);
CREATE VIEW IF NOT EXISTS v1 AS SELECT * FROM t1 WHERE id>10;
INSERT INTO t1 VALUES (5), (8), (10), (20), (30);
SELECT * FROM t1;
id
5
8
10
20
30
SELECT * FROM v1;
id
20
30
CREATE VIEW v1 AS SELECT * FROM t1 WHERE id>11;
ERROR 42S01: Table 'v1' already exists
SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME='v1';
VIEW_DEFINITION
select `test`.`t1`.`id` AS `id` from `test`.`t1` where (`test`.`t1`.`id` > 10)
CREATE VIEW IF NOT EXISTS v1 AS SELECT * FROM t1 WHERE id>12;
Warnings:
Note 1050 Table 'v1' already exists
SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME='v1';
VIEW_DEFINITION
select `test`.`t1`.`id` AS `id` from `test`.`t1` where (`test`.`t1`.`id` > 10)
CREATE OR REPLACE VIEW IF NOT EXISTS v1 AS SELECT * FROM t1 WHERE id>13;
ERROR HY000: Incorrect usage of OR REPLACE and IF NOT EXISTS
SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME='v1';
VIEW_DEFINITION
select `test`.`t1`.`id` AS `id` from `test`.`t1` where (`test`.`t1`.`id` > 10)
CREATE OR REPLACE VIEW v1 AS SELECT * FROM t1 WHERE id>14;
SELECT VIEW_DEFINITION FROM INFORMATION_SCHEMA.VIEWS WHERE TABLE_NAME='v1';
VIEW_DEFINITION
select `test`.`t1`.`id` AS `id` from `test`.`t1` where (`test`.`t1`.`id` > 14)
INSERT INTO t1 VALUES (50), (80), (3), (2), (40);
SELECT * FROM t1;
id
5
8
10
20
30
50
80
3
2
40
SELECT * FROM v1;
id
20
30
50
80
40
DROP VIEW IF EXISTS v1;
DROP VIEW IF EXISTS v1;
Warnings:
Note 1051 Unknown table 'test.v1'
DROP TABLE t1;
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