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#
# MDEV-14012 - sql_mode=Oracle: substr(): treat position 0 as position 1
# MDEV-10574 - sql_mode=Oracle: return null instead of empty string
#
SET sql_mode=ORACLE;
SELECT SUBSTR('abc',2,1),SUBSTR('abc',1,1), SUBSTR('abc',0,1) FROM dual;
SUBSTR('abc',2,1) SUBSTR('abc',1,1) SUBSTR('abc',0,1)
b a a
SELECT SUBSTR('abc',2),SUBSTR('abc',1), SUBSTR('abc',0) FROM dual;
SUBSTR('abc',2) SUBSTR('abc',1) SUBSTR('abc',0)
bc abc abc
SELECT SUBSTR(null,2,1),SUBSTR(null,1), SUBSTR(null,0) FROM dual;
SUBSTR(null,2,1) SUBSTR(null,1) SUBSTR(null,0)
NULL NULL NULL
SELECT SUBSTR('abc',-2),SUBSTR('abc',-1), SUBSTR('abc',-0) FROM dual;
SUBSTR('abc',-2) SUBSTR('abc',-1) SUBSTR('abc',-0)
bc c abc
SELECT SUBSTR('abc',-2,1),SUBSTR('abc',-1,1), SUBSTR('abc',-0,1) FROM dual;
SUBSTR('abc',-2,1) SUBSTR('abc',-1,1) SUBSTR('abc',-0,1)
b c a
SELECT SUBSTR('abc',null) FROM dual;
SUBSTR('abc',null)
NULL
SELECT SUBSTR('abc',2,null),SUBSTR('abc',1,null), SUBSTR('abc',0,null) FROM dual;
SUBSTR('abc',2,null) SUBSTR('abc',1,null) SUBSTR('abc',0,null)
NULL NULL NULL
SELECT SUBSTR('abc',2,0),SUBSTR('abc',1,0), SUBSTR('abc',0,0) FROM dual;
SUBSTR('abc',2,0) SUBSTR('abc',1,0) SUBSTR('abc',0,0)
NULL NULL NULL
SELECT SUBSTR('abc',2,-1),SUBSTR('abc',1,-1), SUBSTR('abc',0,-1) FROM dual;
SUBSTR('abc',2,-1) SUBSTR('abc',1,-1) SUBSTR('abc',0,-1)
NULL NULL NULL
SELECT SUBSTR(SPACE(0),1) FROM DUAL;
SUBSTR(SPACE(0),1)
NULL
CREATE TABLE t1 (c1 VARCHAR(10),start INTEGER, length INTEGER);
INSERT INTO t1 VALUES ('abc', 1, 1);
INSERT INTO t1 VALUES ('abc', 0, 1);
INSERT INTO t1 VALUES (null, 1, 1);
INSERT INTO t1 VALUES (null, 0, 1);
INSERT INTO t1 VALUES ('abc', 1, 0);
INSERT INTO t1 VALUES ('abc', 0, 0);
INSERT INTO t1 VALUES (null, 1, 0);
INSERT INTO t1 VALUES (null, 0, 0);
INSERT INTO t1 VALUES ('abc', 1, -1);
INSERT INTO t1 VALUES ('abc', 0, -1);
INSERT INTO t1 VALUES (null, 1, -1);
INSERT INTO t1 VALUES (null, 0, -1);
INSERT INTO t1 VALUES (SPACE(0), 0, 1);
SELECT SUBSTR(c1,start,length) FROM t1;
SUBSTR(c1,start,length)
a
a
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
NULL
DROP TABLE t1;
CREATE TABLE t1 (c1 VARCHAR(10) NOT NULL);
CREATE TABLE t2 AS SELECT SUBSTR(C1,1,1) AS C1 from t1;
SHOW CREATE TABLE t2;
Table Create Table
t2 CREATE TABLE "t2" (
"C1" varchar(1) DEFAULT NULL
)
DROP TABLE t2;
DROP TABLE t1;
EXPLAIN EXTENDED SELECT SUBSTR('abc',2,1) ;
id select_type table type possible_keys key key_len ref rows filtered Extra
1 SIMPLE NULL NULL NULL NULL NULL NULL NULL NULL No tables used
Warnings:
Note 1003 select oracle_schema.substr('abc',2,1) AS "SUBSTR('abc',2,1)"
CREATE VIEW v1 AS SELECT SUBSTR('abc',2,1) ;
SHOW CREATE VIEW v1;
View Create View character_set_client collation_connection
v1 CREATE VIEW "v1" AS select substr('abc',2,1) AS "SUBSTR('abc',2,1)" latin1 latin1_swedish_ci
SELECT * FROM v1;
SUBSTR('abc',2,1)
b
DROP VIEW v1;
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