Fix two regexes related to SQL create statement parsing

[d-Rickyy-b]

• Do only one thing
• Non breaking API changes
• Tested

What did this pull request do?

Fixes two regex issues that prevented the proper parsing of SQL create statements. Fixes #139. For a more detailed description, please check the linked issue.

[d-Rickyy-b]

Regex 1 - Matching full SQL create statement:

• Old: https://regex101.com/r/NN3LXe/1
• New: https://regex101.com/r/kDbJrU/1

Regex 2 - Renaming table to __temp:

• Old: https://regex101.com/r/vTLBLz/1
• New: https://regex101.com/r/MIfBQJ/1

[jinzhu]

Hello @d-Rickyy-b

Thank you for your PR, can you help to add more tests?

Thank you.

[d-Rickyy-b]

Hi @jinzhu, I added some tests, although the code in the migrator file is not easily testable.

Btw. could you explain to me, why the sqliteSeparator contains \t? Is there any valid reason to it? I couldn't find any explanation by checking git blame.

sqlite/ddlmod.go

Line 15 in cb2c532

sqliteSeparator = "`|\"|'|\t"

This \t is part of another parsing problem related to (multiple) tab characters being part the DDL.
Also there are quite some potential issues related to whitespaces everywhere where you check for a literal space character followed by keywords:

sqlite/ddlmod.go

Line 133 in cb2c532

if strings.Contains(matchUpper, " NOT NULL") {

sqlite/ddlmod.go

Line 135 in cb2c532

} else if strings.Contains(matchUpper, " NULL") {

sqlite/ddlmod.go

Line 138 in cb2c532

if strings.Contains(matchUpper, " UNIQUE") {

sqlite/ddlmod.go

Line 141 in cb2c532

if strings.Contains(matchUpper, " PRIMARY") {

These probably should be replaced with regexes and \s+ instead of literal spaces.