Ruby正則表達式 - 提取字

Question

我想從SQL查詢中提取表名。

SELECT col1, col2, count(1) as count_all,  FROM  tbl1, tbl2 where condition order by column 

我想格蘭結果["tbl1", "tbl2"]

這是沒有必要的，將有多個表查詢。在這種情況下，查詢將

SELECT col1, col2, count(1) as count_all,  FROM  tbl1 where condition order by column 

和預期結果["tbl1"]

提前感謝！

Answer 1

請注意，這可能會匹配SQL字符串中的內容，因此並不完美。

test = [ 
"SELECT col1, col2, count(1) as count_all FROM tbl1, tbl2 where condition order by column", 
"SELECT col1, col2, count(1) as count_all FROM tbl1 where condition order by column", 
"SELECT col1, col2, count(1) as count_all FROM tbl1", 
] 
tests.map { |str| str.match(/\s*from\s*([a-z_0-9]+(?:,\s*[a-z_0-9]+)*)\b/i); $1 } 
#=> ["tbl1, tbl2", "tbl1", "tbl1"]