Regular Expressions 101

Explanation
Pro

Positive Lookbehind(?<="NULL","0","0","0",",","1",",)

"NULL","0","0","0",",","1",",the literal text "NULL","0","0","0",",","1",", (case sensitive)

Non-Capturing Group(?:"([^"]+)",?)

"the literal " (34₁₀ / 42₈ / 22₁₆)

Group 1([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

,?optionally matches the literal , (44₁₀ / 54₈ / 2C₁₆)

Non-Capturing Group(?:"([^"]+)",?)?

?repeats the group contents below at most once:

"the literal " (34₁₀ / 42₈ / 22₁₆)

Group 2([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

,?optionally matches the literal , (44₁₀ / 54₈ / 2C₁₆)

Non-Capturing Group(?:"([^"]+)",?)?

?repeats the group contents below at most once:

"the literal " (34₁₀ / 42₈ / 22₁₆)

Group 3([^"]+)

Negated Character Class[^"]+

+matches at least one character outside the set below:

"the literal " (34₁₀ / 42₈ / 22₁₆)

,?optionally matches the literal , (44₁₀ / 54₈ / 2C₁₆)

Positive Lookahead(?=,"D\$")

,"Dthe literal text ,"D (case sensitive)

\$the literal $ (36₁₀ / 44₈ / 24₁₆)

"the literal " (34₁₀ / 42₈ / 22₁₆)

Global pattern flags

g modifier: global. Finds all matches instead of stopping after the first

m modifier: multiline. Causes ^ and $ to match the start and end of each line, not only the start and end of the string

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25 tokens

(?<="NULL","0","0","0",",","1",",)(?:"([^"]+)",?)(?:"([^"]+)",?)?(?:"([^"]+)",?)?(?=,"D\$")

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