Simple database wrapper for Microsoft SQL Server, MySQL, PostgreSQL, and Sqlite written in C# supporting dynamic query building and nesting using expressions.
MIT License
DatabaseWrapper is the EASIEST and FASTEST way to get a data-driven application up and running using SQL Server, MySQL, PostgreSQL, or Sqlite.
For a sample app exercising this library, refer to the numerous Test
projects contained within the solution.
Core features:
Special thanks to those who have helped contribute or otherwise improve the library!
@shawty @constantinje @thedarklort @l-404-l @igrgurina @Vaelek @treyhay31 @daoye @twobytescy @rinkusahu1 @Skimmenthal13
Use of parameterized queries vs building queries dynamically is a sensitive subject. Proponents of parameterized queries have data on their side - that parameterization does the right thing to prevent SQL injection and other issues. I do not disagree with them. However, it is worth noting that with proper care, you CAN build systems that allow you to dynamically build queries, and you SHOULD do so as long as you build in the appropriate safeguards.
If you find an injection attack that will defeat the sanitization layer built into this project, please let me know!
Refer to the test project for a more complete example with sample table setup scripts.
using DatabaseWrapper;
using DatabaseWrapper.Core;
using ExpressionTree;
DatabaseClient client = null;
// Sqlite
client = new DatabaseClient("[databasefilename]");
// SQL Server, MySQL, or PostgreSQL
client = new DatabaseClient(DbTypes.SqlServer, "[hostname]", [port], "[user]", "[password]", "[databasename]");
client = new DatabaseClient(DbTypes.Mysql, "[hostname]", [port], "[user]", "[password]", "[databasename]");
client = new DatabaseClient(DbTypes.Postgresql, "[hostname]", [port], "[user]", "[password]", "[databasename]");
// SQL Express
client = new DatabaseClient(DbTypes.SqlServer, "[hostname]", [port], "[user]", "[password]", "[instance]", "[databasename]");
// some variables we'll be using
Dictionary<string, object> d;
Expr e;
List<string> fields;
DataTable result;
// add a record
d = new Dictionary<string, object>();
d.Add("firstName", "Joel");
d.Add("lastName", "Christner");
d.Add("notes", "Author");
result = client.Insert("person", d);
result = await client.InsertAsync("person", d);
// update a record
d = new Dictionary<string, object>();
d.Add("notes", "The author :)");
e = new Expr("firstName", OperatorEnum.Equals, "Joel");
client.Update("person", d, e);
await client.UpdateAsync("person", d, e);
// retrieve 10 records
fields = new List<string> { "firstName", "lastName" }; // leave null for *
e = new Expr("lastName", OperatorEnum.Equals, "Christner");
ResultOrder[] order = new ResultOrder[1];
order = new ResultOrder("firstName", OrderDirectionEnum.Ascending)
result = client.Select("person", 0, 10, fields, e, order);
result = await client.SelectAsync("person", 0, 10, fields, e, order);
// delete a record
e = new Expr("firstName", Operators.Equals, "Joel");
client.Delete("person", e);
await client.DeleteAsync("person", e);
// execute a raw query
result = client.Query("SELECT customer_id FROM customer WHERE customer_id > 10");
result = await client.QueryAsync("SELECT customer_id FROM customer WHERE customer_id > 10");
Expressions, i.e. the Expr
class from ExpressionTree
, can be nested in either the Left
or Right
properties. Conversion from Expr
to a WHERE clause uses recursion, so you have a good degree of flexibility in building your expressions in terms of depth.
Expr e = new Expr {
Left = new Expr("age", OperatorEnum.GreaterThan, 30),
Operator = Operators.And,
Right = new Expr("height", OperatorEnum.LessThan, 74)
};
Use IndexStart
, MaxResults
, and ResultOrder[]
to retrieve paginated results. The query will retrieve maxResults records starting at row number indexStart using an ordering based on orderByClause. See the example in the DatabaseWrapperTest project.
IMPORTANT: When doing pagination with SQL Server, you MUST specify an ResultOrder[]
.
ResultOrder[] order = new ResultOrder[1];
order = new ResultOrder("firstName", OrderDirectionEnum.Ascending);
DataTable result = client.Select("person", 5, 10, null, e, order);
We added a simple static method for this which you can use when building expressions (or elsewhere). An object method exists as well.
string ts = client.Timestamp(DateTime.Now);
// 08/23/2016 05:34:32.4349034 PM
string tso = client.Timestamp(DateTime.Now);
// 2016-08-23 17:34:32.446913
When using database-specific classes DatabaseWrapper.Mysql
, DatabaseWrapper.Postgresql
, DatabaseWrapper.SqlServer
, or DatabaseWrapper.Sqlite
, the constructor is simplified from what is shown above.
For Sqlite:
DatabaseClient client = new DatabaseClient("[databasefilename]");
For SQL Server, MySQL, or PostgreSQL:
DatabaseClient client = new DatabaseClient(DbTypes.SqlServer, "[hostname]", [port], "[user]", "[password]", "[databasename]");
DatabaseClient client = new DatabaseClient(DbTypes.Mysql, "[hostname]", [port], "[user]", "[password]", "[databasename]");
DatabaseClient client = new DatabaseClient(DbTypes.Postgresql, "[hostname]", [port], "[user]", "[password]", "[databasename]");
For SQL Server Express:
DatabaseClient client = new DatabaseClient(DbTypes.SqlServer, "[hostname]", [port], "[user]", "[password]", "[instance]", "[databasename]");
IndexStart
and MaxResults
are supplied demands use of ResultOrder[]
.runtimes
folder into your project output directory. This directory is automatically created when building for .NET Core. To get this folder, build the Test.Sqlite
project and navigate to the bin/debug/netcoreapp*
directory. Then copy the runtimes
folder into the project output directory of your .NET Framework application.Refer to CHANGELOG.md.