Split text by symbol: Difference between revisions
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=== MySQL Approach === | === MySQL Approach === | ||
{{exclaim}} Only one symbol was allowed. The following query will get the last element if there are more than two symbols. | |||
# to get the first string ( 25.040215 ): {{code | code=SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', <span style="color:red">1</span>))}} | # to get the first string ( 25.040215 ): {{code | code=SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', <span style="color:red">1</span>))}} | ||
# to get the second string ( 121.512532 ): {{code | code=SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', <span style="color:red">-1</span>))}} | # to get the second string ( 121.512532 ): {{code | code=SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', <span style="color:red">-1</span>))}} | ||
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CREATE TABLE tbl(str varchar(50)); | CREATE TABLE tbl(str varchar(50)); | ||
INSERT INTO tbl VALUES('25.040215, 121.512532'); | INSERT INTO tbl VALUES('25.040215, 121.512532'); | ||
INSERT INTO tbl VALUES('123.456'); /*bad data*/ | INSERT INTO tbl VALUES('25.040215, 121.512532, 999.999'); /*bad data: 2 or more symbols*/ | ||
INSERT INTO tbl VALUES('123.456'); /*bad data: no symbol exists*/ | |||
SELECT TRIM(SUBSTRING_INDEX(str ,',', 1)), TRIM(SUBSTRING_INDEX(str ,',', -1)) FROM tbl WHERE str LIKE '%,%'; | SELECT TRIM(SUBSTRING_INDEX(str ,',', 1)), TRIM(SUBSTRING_INDEX(str ,',', -1)) FROM tbl WHERE str LIKE '%,%'; | ||
</pre> | </pre> | ||
Revision as of 18:09, 4 November 2015
Split text by symbol (another string, also called delimiter or separator)
Approaches
list of equivalent approaches to split text by symbol
- MySQL: MySQL SUBSTRING_INDEX() function - w3resource
- Excel: (1) parse data (資料剖析)
only allowed one character used as separator! (2) LEFT, RIGHT, FIND, LEN (3) MOD, FIND, LEN - PHP: explode function
Example
Task: Split the position e.g. 25.040215, 121.512532 by the comma ( , ) to obtain the latitude (1st string) and longitude (2nd string).
Expected output:
- 25.040215
- 121.512532
MySQL Approach
Only one symbol was allowed. The following query will get the last element if there are more than two symbols.
- to get the first string ( 25.040215 ):
SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', 1)) - to get the second string ( 121.512532 ):
SELECT TRIM(SUBSTRING_INDEX('25.040215, 121.512532' ,',', -1))
CREATE TABLE tbl(str varchar(50));
INSERT INTO tbl VALUES('25.040215, 121.512532');
INSERT INTO tbl VALUES('25.040215, 121.512532, 999.999'); /*bad data: 2 or more symbols*/
INSERT INTO tbl VALUES('123.456'); /*bad data: no symbol exists*/
SELECT TRIM(SUBSTRING_INDEX(str ,',', 1)), TRIM(SUBSTRING_INDEX(str ,',', -1)) FROM tbl WHERE str LIKE '%,%';
Excel Approach
1: parse data
- instruction with images: Split text into different cells - Excel
2: SUBSTRING_INDEX
| A | B | C | |
|---|---|---|---|
| 1 | 25.040215, 121.512532 | 25.040215 |
121.512532 |
If the data set is perfect
- to get the first string ( 25.040215 ): B1 =
MID( A1, 1, FIND(",", A1)-1) - to get the second string ( 121.512532 ): C1 =
MID( A1, FIND(",", A1)+1, LEN(A1))
if the data set was mixed with empty values. Return empty if the value is empty.
- to get the first string ( 25.040215 ): B1 =
IF(ISERROR(MID(A1, 1, FIND(",", A1)-1)), "", MID(A1, 1, FIND(",", A1)-1)) - to get the second string ( 121.512532 ): C1 =
IF(ISERROR(TRIM(MID(A1, FIND(",", A1)+1, LEN(A1)))), "", TRIM(MID(A1, FIND(",", A1)+1, LEN(A1)))
online demo (allow to edit)