CREATE TABLE t (c1 INT PRIMARY KEY, c2 INT NOT NULL, c3 INT) ENGINE=InnoDB;
INSERT INTO t VALUES (1,2,3),(4,5,6),(7,8,9);
ALTER TABLE t CHANGE c1 c1 INT NULL FIRST, ALGORITHM=INPLACE;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 0
ALTER TABLE t MODIFY c3 INT NOT NULL, ALGORITHM=INPLACE;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 0
ALTER TABLE t CHANGE c2 c2 INT, CHANGE c2 c2 INT NOT NULL; ERROR42S22: Unknown column 'c2' in 't'
ALTER TABLE t MODIFY c2 INT, MODIFY c2 INT NOT NULL; ERROR42S22: Unknown column 'c2' in 't'
ALTER TABLE t MODIFY c2 INT UNSIGNED, MODIFY c2 INT; ERROR42S22: Unknown column 'c2' in 't'
ALTER TABLE t MODIFY c2 CHAR(1) NOT NULL, MODIFY c2 INT NOT NULL; ERROR42S22: Unknown column 'c2' in 't'
ALTER TABLE t CHANGE c2 c2 INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 0
ALTER TABLE t MODIFY c2 INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 0
connect con1,localhost,root,,;
UPDATE t SET c2=NULL; ERROR23000: Column 'c2' cannot be null
SELECT * FROM t;
c1 c2 c3 123 456 789
connection default;
ALTER TABLE t MODIFY c2 INT, ALGORITHM=INPLACE;
connection con1;
BEGIN;
UPDATE t SET c2=NULL;
SELECT * FROM t;
c1 c2 c3 1 NULL 3 4 NULL 6 7 NULL 9
ROLLBACK;
SELECT * FROM t;
c1 c2 c3 123 456 789
disconnect con1;
connection default;
ALTER TABLE t MODIFY c2 INT NULL, ALGORITHM=INPLACE;
SELECT * FROM INFORMATION_SCHEMA.INNODB_SYS_TABLES
WHERE NAME='test/t';
TABLE_ID NAME FLAG N_COLS SPACE ROW_FORMAT ZIP_PAGE_SIZE SPACE_TYPE
# test/t 336 # Dynamic 0 Single
DROP TABLE t;
CREATE TABLE t1(c1 INT) ENGINE=InnoDB;
ALTER TABLE t1 ADD CONSTRAINT UNIQUE KEY i1(c1);
ALTER TABLE t1 CHANGE c1 c1 INT NOT NULL,ADD KEY(c1);
DROP TABLE t1;
#
# MDEV-18732 InnoDB: ALTER IGNORE returns error for NULL
#
CREATE TABLE t1(c INT) ENGINE=InnoDB;
INSERT INTO t1 VALUES (NULL);
ALTER IGNORE TABLE t1 MODIFY c INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
INSERT INTO t1 VALUES (NULL); ERROR23000: Column 'c' cannot be null
SELECT * FROM t1;
c 0
DROP TABLE t1;
CREATE TABLE t1(c INT) ENGINE=InnoDB;
INSERT INTO t1 VALUES (NULL),(1),(1);
ALTER IGNORE TABLE t1 ADD UNIQUE(c);
affected rows: 3
info: Records: 3 Duplicates: 1 Warnings: 0
ALTER IGNORE TABLE t1 ADD PRIMARY KEY(c);
affected rows: 2
info: Records: 2 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
SELECT * FROM t1;
c 0 1
DROP TABLE t1;
CREATE TABLE t1(c INT, g INT AS (c) PERSISTENT) ENGINE=InnoDB;
CREATE TABLE t2(c INT, v INT AS (c) VIRTUAL) ENGINE=InnoDB;
CREATE TABLE t3(c INT, v INT AS (c) VIRTUAL, INDEX(v)) ENGINE=InnoDB;
INSERT INTO t1 SET c=NULL;
INSERT INTO t2 SET c=NULL;
INSERT INTO t3 SET c=NULL; SET @old_sql_mode = @@sql_mode; SET sql_mode = '';
ALTER TABLE t1 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
ALTER TABLE t2 MODIFY c INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
ALTER TABLE t3 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1 SET sql_mode = @old_sql_mode;
SELECT * FROM t1;
c g 00
SELECT * FROM t2;
c v 00
SELECT * FROM t3;
c v 00
SELECT v FROM t3 FORCE INDEX(v);
v 0
CHECK TABLE t1,t2,t3;
Table Op Msg_type Msg_text
test.t1 check status OK
test.t2 check status OK
test.t3 check status OK
DROP TABLE t1,t2,t3;
CREATE TABLE t1(c INT, g INT AS (c) PERSISTENT) ENGINE=InnoDB;
CREATE TABLE t2(c INT, v INT AS (c) VIRTUAL) ENGINE=InnoDB;
CREATE TABLE t3(c INT, v INT AS (c) VIRTUAL, INDEX(v)) ENGINE=InnoDB;
INSERT INTO t1 SET c=NULL;
INSERT INTO t2 SET c=NULL;
INSERT INTO t3 SET c=NULL;
ALTER IGNORE TABLE t1 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
ALTER IGNORE TABLE t2 MODIFY c INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
ALTER IGNORE TABLE t3 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 1
Warnings:
Warning 1265 Data truncated for column 'c' at row 1
SELECT * FROM t1;
c g 00
SELECT * FROM t2;
c v 00
SELECT * FROM t3;
c v 00
SELECT v FROM t3 FORCE INDEX(v);
v 0
CHECK TABLE t1,t2,t3;
Table Op Msg_type Msg_text
test.t1 check status OK
test.t2 check status OK
test.t3 check status OK
DROP TABLE t1,t2,t3;
CREATE TABLE t1(c INT, g INT AS (c) PERSISTENT) ENGINE=InnoDB;
CREATE TABLE t2(c INT, v INT AS (c) VIRTUAL) ENGINE=InnoDB;
CREATE TABLE t3(c INT, v INT AS (c) VIRTUAL, INDEX(v)) ENGINE=InnoDB;
INSERT INTO t1 SET c=NULL;
INSERT INTO t2 SET c=NULL;
INSERT INTO t3 SET c=NULL;
ALTER TABLE t1 MODIFY c INT NOT NULL; ERROR01000: Data truncated for column 'c' at row 1
ALTER TABLE t2 MODIFY c INT NOT NULL; ERROR01000: Data truncated for column 'c' at row 1
ALTER TABLE t3 MODIFY c INT NOT NULL; ERROR01000: Data truncated for column 'c' at row 1
UPDATE t1 SET c=0;
UPDATE t2 SET c=0;
UPDATE t3 SET c=0;
ALTER TABLE t1 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 0
ALTER TABLE t2 MODIFY c INT NOT NULL;
affected rows: 0
info: Records: 0 Duplicates: 0 Warnings: 0
ALTER TABLE t3 MODIFY c INT NOT NULL;
affected rows: 1
info: Records: 1 Duplicates: 0 Warnings: 0
SELECT * FROM t1;
c g 00
SELECT * FROM t2;
c v 00
SELECT * FROM t3;
c v 00
DROP TABLE t1,t2,t3;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.22 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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