TShock/TShockAPI/DB/Queries/PostgresQueryCreator.cs
Sakura Akeno Isayeki f28f1bf536
feat(db): Add PostgreSQL query creator implementation
Implements a query creator for PostgreSQL, allowing for proper database type mapping and table creation functionalities.

Enhances the library's database support by incorporating PostgreSQL-specific features such as SERIAL/BIGSERIAL for auto-increment columns and improved escape handling for table names.

Improves the extensibility and compatibility of the database framework with different SQL databases.
2025-04-28 14:09:10 +02:00

89 lines
2.8 KiB
C#

/*
TShock, a server mod for Terraria
Copyright (C) 2011-2019 Pryaxis & TShock Contributors
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
using System;
using System.Collections.Generic;
using System.Linq;
using MySql.Data.MySqlClient;
namespace TShockAPI.DB.Queries;
/// <summary>
/// Query Creator for PostgreSQL
/// </summary>
public class PostgresQueryCreator : GenericQueryCreator
{
/// <inheritdoc />
public override string DbTypeToString(MySqlDbType type, int? length) => type switch
{
MySqlDbType.VarChar when length is not null => "VARCHAR({0})".SFormat(length),
MySqlDbType.String when length is not null => "CHAR({0})".SFormat(length),
MySqlDbType.Text => "TEXT",
MySqlDbType.TinyText => "TEXT",
MySqlDbType.MediumText => "TEXT",
MySqlDbType.LongText => "TEXT",
MySqlDbType.Float => "REAL",
MySqlDbType.Double => "DOUBLE PRECISION",
MySqlDbType.Int32 => "INT",
MySqlDbType.Int64 => "BIGINT",
MySqlDbType.DateTime => "TIMESTAMP",
_ => throw new NotImplementedException(Enum.GetName(typeof(MySqlDbType), type))
};
/// <inheritdoc />
protected override string EscapeTableName(string table) => table.SFormat("\"{0}\"", table);
/// <inheritdoc />
public override string CreateTable(SqlTable table)
{
ValidateSqlColumnType(table.Columns);
IEnumerable<string> columns = table.Columns.Select(c =>
{
// Handle PostgreSQL-specific auto-increment using SERIAL/BIGSERIAL
string dataType;
if (c.AutoIncrement)
{
dataType = c.Type is MySqlDbType.Int32 ? "SERIAL" : "BIGSERIAL";
}
else
{
dataType = DbTypeToString(c.Type, c.Length);
}
return "\"{0}\" {1} {2} {3} {4}".SFormat(c.Name,
dataType,
c.Primary ? "PRIMARY KEY" : "",
c.NotNull && !c.AutoIncrement ? "NOT NULL" : "", // SERIAL implies NOT NULL
c.DefaultCurrentTimestamp ? "DEFAULT CURRENT_TIMESTAMP" : "");
});
string[] uniques = table.Columns
.Where(c => c.Unique).Select(c => $"\"{c.Name}\"")
.ToArray(); // No re-enumeration
return "CREATE TABLE {0} ({1} {2})".SFormat(EscapeTableName(table.Name),
string.Join(", ", columns),
uniques.Any() ? ", UNIQUE({0})".SFormat(string.Join(", ", uniques)) : "");
}
/// <inheritdoc />
public override string RenameTable(string from, string to) => /*lang=postgresql*/"ALTER TABLE {0} RENAME TO {1}".SFormat(from, to);
}