.NET SQL Parser SDK for C# and VB.NET

1. Reference the package

<!-- your .csproj -->
<ItemGroup>
  <PackageReference Include="gudusoft.gsqlparser" Version="4.1.0.7" />
</ItemGroup>

4.1.0.7 is the current version on nuget.org, so dotnet add package gudusoft.gsqlparser resolves to it. This is the trial build: it parses statements up to 10,000 characters and parse() returns -1 above that — fine for individual queries, not for a real stored procedure. See below for an evaluation build without the limit. Air-gapped builds can restore the same package from an internal feed or a local folder.

2. Parse one SQL statement

using gudusoft.gsqlparser;

string sql = @"select c.customer_id, sum(o.amount) total
               from customers c join orders o on c.id = o.customer_id
               group by c.customer_id";

TGSqlParser parser = new TGSqlParser(EDbVendor.dbvoracle);
parser.sqltext = sql;
int result = parser.parse();

3. Handle parser errors clearly

if (result != 0)
{
    Console.WriteLine(parser.Errormessage);
    // e.g. syntax error, state:90(10101) near: from(1,8)
    return;
}

Errors carry the offending token with line and column position, so you can point a user straight at the problem.

4. Inspect AST, tables, and columns

using gudusoft.gsqlparser.nodes;

for (int i = 0; i < parser.sqlstatements.size(); i++)
{
    TCustomSqlStatement stmt = parser.sqlstatements.get(i);
    Console.WriteLine(stmt.sqlstatementtype);            // sstselect

    for (int t = 0; t < stmt.tables.size(); t++)
    {
        TTable table = stmt.tables.getTable(t);
        Console.WriteLine(table.FullName + " " + table.AliasName);
        // customers c
        // orders o
    }

    for (int c = 0; c < stmt.ResultColumnList.size(); c++)
    {
        TResultColumn rc = stmt.ResultColumnList.getResultColumn(c);
        Console.WriteLine(rc.Expr + (rc.AliasClause != null ? " AS " + rc.AliasClause : ""));
        // c.customer_id
        // sum(o.amount) AS total
    }
}