CREATE TABLE t1 (a CHAR(8), id INT, PRIMARY KEY (a,id)) COLLATE utf8_nopad_bin
ENGINE=InnoDB ROW_FORMAT=REDUNDANT;
INSERT INTO t1 VALUES ('',1);
ALTER TABLE t1 ROW_FORMAT=DYNAMIC;
INSERT INTO t1 VALUES ('',2);
ALTER TABLE t1 ROW_FORMAT=REDUNDANT;
DROP TABLE t1;
#
# MDEV-26743 InnoDB: CHAR+nopad does not work well
#
#
# Basic Latin letter vs equal accented letter
# SET NAMES utf8mb3;
CREATE TABLE t1 (a CHAR(2), PRIMARY KEY(a)) COLLATE utf8_unicode_nopad_ci ENGINE=InnoDB ROW_FORMAT=COMPACT;
INSERT INTO t1 VALUES ('a'),('ä'); ERROR23000: Duplicate entry 'ä' for key 'PRIMARY'
DROP TABLE t1;
#
# Two letters vs equal (but space padded) expansion
#
CREATE TABLE t1 (a CHAR(2), PRIMARY KEY(a)) COLLATE utf8_unicode_nopad_ci ENGINE=InnoDB ROW_FORMAT=COMPACT;
INSERT INTO t1 VALUES ('ss'),('ß'); SET sql_mode=PAD_CHAR_TO_FULL_LENGTH;
SELECT HEX(a) FROM t1;
HEX(a) 7373
C39F20 SET sql_mode=DEFAULT;
DROP TABLE t1;
#
# Basic Latin letter (but followed by an ignorable character) vs equal accented letter
# SET NAMES utf8mb3;
CREATE TABLE t1 (a CHAR(3), PRIMARY KEY(a)) CHARACTER SET utf8mb3 COLLATE utf8mb3_unicode_nopad_ci ENGINE=InnoDB ROW_FORMAT=COMPACT;
INSERT INTO t1 VALUES (CONCAT('a',_utf8mb3 0x01)),('ä'); SET sql_mode=PAD_CHAR_TO_FULL_LENGTH;
SELECT HEX(a) FROM t1 ORDER BY HEX(a);
HEX(a) 610120
C3A42020 SET sql_mode=DEFAULT;
DROP TABLE t1; SET NAMES utf8mb3;
CREATE TABLE t1 (a CHAR(2), PRIMARY KEY(a)) COLLATE utf8_unicode_nopad_ci ENGINE=InnoDB ROW_FORMAT=COMPACT;
INSERT INTO t1 VALUES (CONCAT('a',_utf8mb3 0x01)),('ä'); SET sql_mode=PAD_CHAR_TO_FULL_LENGTH;
SELECT HEX(a) FROM t1 ORDER BY HEX(a);
HEX(a) 6101
C3A420 SET sql_mode=DEFAULT;
DROP TABLE t1;
Messung V0.5 in Prozent
¤ Dauer der Verarbeitung: 0.11 Sekunden
(vorverarbeitet am 2026-10-08)
¤
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