import Foundation
let pattern = #"^(?=\s*SELECT\s+([\s\S]*?)(?=\s+(?:INTO|FROM|WHERE|GROUP\s+BY|HAVING|ORDER\s+BY)\s))(?=(?:[\s\S]*?\s+INTO\s+([\S]+)\s*)?)(?=(?:[\s\S]*?\s+FROM\s+([\s\S]*?)(?=\s+(?:WHERE|GROUP\s+BY|HAVING|ORDER\s+BY)\s)))(?=(?:[\s\S]*?\s+WHERE\s+([\s\S]*?)(?=\s+(?:GROUP\s+BY|HAVING|ORDER\s+BY)\s)))(?=(?:[\s\S]*?\s+GROUP\s+BY\s+([\s\S]*?)(?=\s+(?:HAVING|ORDER\s+BY)\s))?)(?=(?:[\s\S]*?\s+HAVING\s+([\s\S]*?)(?=\s+ORDER\s+BY\s))?)(?=(?:[\s\S]*?\s+ORDER\s+BY\s+([\s\S]*?)(?=\s*$))).*$"#
let regex = try! NSRegularExpression(pattern: pattern, options: .anchorsMatchLines)
let testString = #"""
SELECT
t1.dummy1,
t1.dummy2,
t1.dummy3
INTO
testResult
FROM
(test1 t1
INNER JOIN test2 t2 ON t1.dummy4 = t2.dummy4)
INNER JOIN test3 t3 ON t2.dummy9 = t3.dummy9
WHERE
t2.dummy6 = 'abc'
AND t3.dummy10 <> 'def'
AND t1.dummy11 = 'ghi'
AND t2.dummy12 IS NULL
HAVING 1=1
ORDER BY 1;
"""#
let stringRange = NSRange(location: 0, length: testString.utf16.count)
let matches = regex.matches(in: testString, range: stringRange)
var result: [[String]] = []
for match in matches {
var groups: [String] = []
for rangeIndex in 1 ..< match.numberOfRanges {
let nsRange = match.range(at: rangeIndex)
guard !NSEqualRanges(nsRange, NSMakeRange(NSNotFound, 0)) else { continue }
let string = (testString as NSString).substring(with: nsRange)
groups.append(string)
}
if !groups.isEmpty {
result.append(groups)
}
}
print(result)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for Swift 5.2, please visit: https://developer.apple.com/documentation/foundation/nsregularexpression