A concise tutorial of SQL statements for Linux---SUBSTRING

The substring function in SQL is used to grab a portion of a field data. The name of this function is not exactly the same in different repositories:

• Mysql:substr (), SUBSTRING ()
• Oracle:substr ()
• SQL server:substring ()

The most frequently used methods are the following (here we use SUBSTR () for example):

SUBSTR (str, POS)

From <str>, select all characters starting from the <pos> position. Please note that this syntax does not apply to SQL Server.

SUBSTR (str, POS, len)

From the <str> <pos> position, select the next <len> characters.

If we have the following table:

Geography Form

Region_name	Store_name
East	Boston
East	New York
West	Los Angeles
West	San Diego

Example 1

SELECT SUBSTR (store_name, 3)
From Geography
WHERE store_name = ' Los Angeles ';

Results:

' s Angeles '

Example 2

SELECT SUBSTR (Store_name, 2, 4)
From Geography
WHERE store_name = ' San Diego ';

Results:

' an D '

Linux measurements such as the following:


reprint Please specify: Xiao Liu

A concise tutorial of SQL statements for Linux---SUBSTRING