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USE test;
DROP TABLE IF EXISTS t1;
CREATE TABLE t1
(
f1 CHAR UNICODE,
f2 CHAR(0) UNICODE,
f3 CHAR(10) UNICODE,
f5 VARCHAR(0) UNICODE,
f6 VARCHAR(255) UNICODE,
f7 VARCHAR(260) UNICODE,
f8 TEXT UNICODE,
f9 TINYTEXT UNICODE,
f10 MEDIUMTEXT UNICODE,
f11 LONGTEXT UNICODE,
PRIMARY KEY(f1)
) ENGINE = NDB;
SELECT * FROM information_schema.columns
WHERE table_schema LIKE 'test%'
ORDER BY table_schema, table_name, column_name;
TABLE_CATALOG TABLE_SCHEMA TABLE_NAME COLUMN_NAME ORDINAL_POSITION COLUMN_DEFAULT IS_NULLABLE DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH NUMERIC_PRECISION NUMERIC_SCALE CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE COLUMN_KEY EXTRA PRIVILEGES COLUMN_COMMENT
NULL test t1 f1 1 NO char 1 2 NULL NULL ucs2 ucs2_general_ci char(1) PRI select,insert,update,references
NULL test t1 f10 9 NULL YES mediumtext 8388607 16777215 NULL NULL ucs2 ucs2_general_ci mediumtext select,insert,update,references
NULL test t1 f11 10 NULL YES longtext 2147483647 4294967295 NULL NULL ucs2 ucs2_general_ci longtext select,insert,update,references
NULL test t1 f2 2 NULL YES char 0 0 NULL NULL ucs2 ucs2_general_ci char(0) select,insert,update,references
NULL test t1 f3 3 NULL YES char 10 20 NULL NULL ucs2 ucs2_general_ci char(10) select,insert,update,references
NULL test t1 f5 4 NULL YES varchar 0 0 NULL NULL ucs2 ucs2_general_ci varchar(0) select,insert,update,references
NULL test t1 f6 5 NULL YES varchar 255 510 NULL NULL ucs2 ucs2_general_ci varchar(255) select,insert,update,references
NULL test t1 f7 6 NULL YES varchar 260 520 NULL NULL ucs2 ucs2_general_ci varchar(260) select,insert,update,references
NULL test t1 f8 7 NULL YES text 32767 65535 NULL NULL ucs2 ucs2_general_ci text select,insert,update,references
NULL test t1 f9 8 NULL YES tinytext 127 255 NULL NULL ucs2 ucs2_general_ci tinytext select,insert,update,references
##########################################################################
# Show the quotient of CHARACTER_OCTET_LENGTH and CHARACTER_MAXIMUM_LENGTH
##########################################################################
SELECT DISTINCT
CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH AS COL_CML,
DATA_TYPE,
CHARACTER_SET_NAME,
COLLATION_NAME
FROM information_schema.columns
WHERE table_schema LIKE 'test%'
AND CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH = 1
ORDER BY CHARACTER_SET_NAME, COLLATION_NAME, COL_CML;
COL_CML DATA_TYPE CHARACTER_SET_NAME COLLATION_NAME
SELECT DISTINCT
CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH AS COL_CML,
DATA_TYPE,
CHARACTER_SET_NAME,
COLLATION_NAME
FROM information_schema.columns
WHERE table_schema LIKE 'test%'
AND CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH <> 1
ORDER BY CHARACTER_SET_NAME, COLLATION_NAME, COL_CML;
COL_CML DATA_TYPE CHARACTER_SET_NAME COLLATION_NAME
2.0000 char ucs2 ucs2_general_ci
2.0000 longtext ucs2 ucs2_general_ci
2.0000 mediumtext ucs2 ucs2_general_ci
2.0000 text ucs2 ucs2_general_ci
2.0000 varchar ucs2 ucs2_general_ci
2.0079 tinytext ucs2 ucs2_general_ci
SELECT DISTINCT
CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH AS COL_CML,
DATA_TYPE,
CHARACTER_SET_NAME,
COLLATION_NAME
FROM information_schema.columns
WHERE table_schema LIKE 'test%'
AND CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH IS NULL
ORDER BY CHARACTER_SET_NAME, COLLATION_NAME, COL_CML;
COL_CML DATA_TYPE CHARACTER_SET_NAME COLLATION_NAME
NULL char ucs2 ucs2_general_ci
NULL varchar ucs2 ucs2_general_ci
--> CHAR(0) is allowed (see manual), and here both CHARACHTER_* values
--> are 0, which is intended behavior, and the result of 0 / 0 IS NULL
SELECT CHARACTER_OCTET_LENGTH / CHARACTER_MAXIMUM_LENGTH AS COL_CML,
TABLE_SCHEMA,
TABLE_NAME,
COLUMN_NAME,
DATA_TYPE,
CHARACTER_MAXIMUM_LENGTH,
CHARACTER_OCTET_LENGTH,
CHARACTER_SET_NAME,
COLLATION_NAME,
COLUMN_TYPE
FROM information_schema.columns
WHERE table_schema LIKE 'test%'
ORDER BY TABLE_SCHEMA, TABLE_NAME, ORDINAL_POSITION;
COL_CML TABLE_SCHEMA TABLE_NAME COLUMN_NAME DATA_TYPE CHARACTER_MAXIMUM_LENGTH CHARACTER_OCTET_LENGTH CHARACTER_SET_NAME COLLATION_NAME COLUMN_TYPE
2.0000 test t1 f1 char 1 2 ucs2 ucs2_general_ci char(1)
NULL test t1 f2 char 0 0 ucs2 ucs2_general_ci char(0)
2.0000 test t1 f3 char 10 20 ucs2 ucs2_general_ci char(10)
NULL test t1 f5 varchar 0 0 ucs2 ucs2_general_ci varchar(0)
2.0000 test t1 f6 varchar 255 510 ucs2 ucs2_general_ci varchar(255)
2.0000 test t1 f7 varchar 260 520 ucs2 ucs2_general_ci varchar(260)
2.0000 test t1 f8 text 32767 65535 ucs2 ucs2_general_ci text
2.0079 test t1 f9 tinytext 127 255 ucs2 ucs2_general_ci tinytext
2.0000 test t1 f10 mediumtext 8388607 16777215 ucs2 ucs2_general_ci mediumtext
2.0000 test t1 f11 longtext 2147483647 4294967295 ucs2 ucs2_general_ci longtext
DROP TABLE t1;
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