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@ -1,514 +0,0 @@
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使用 .net 程序操作数据库
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=======================
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除了使用SQL内核执行SQL语句直接操作数据库，使用最多的是使用用.net程序操作数据库：
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+ ado.net 原生操作
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+ 使用ORM框架，比如 Daper、EFCore、SqlSugar、FreeSQL等
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## 初始化
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```csharp
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#!import "./Base.ipynb"
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//共享
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#r "nuget:Microsoft.Data.SqlClient"
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#r "nuget:MySql.Data"
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#r "nuget:Npgsql"
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#r "nuget:Microsoft.Data.Sqlite"
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#r "nuget:DuckDB.NET.Data.Full"
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#r "nuget:Dapper"
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#r "nuget:Microsoft.EntityFrameworkCore"
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#r "nuget:Microsoft.EntityFrameworkCore.SqlServer"
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#r "nuget:Microsoft.EntityFrameworkCore.Sqlite"
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#r "nuget:Npgsql.EntityFrameworkCore.PostgreSQL"
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#r "nuget:MySql.EntityFrameworkCore"
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//#r "nuget:Pomelo.EntityFrameworkCore.MySql"
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#r "nuget:MongoDB.EntityFrameworkCore"
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global using System.Text.Json;
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global using System.Text.Json.Schema;
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global using System.Text.Json.Serialization;
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global using System.Data;
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global using System.Data.Common;
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global using System.Data.SqlTypes;
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global using System.Data.SqlClient;
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//global using System.Data.OracleClient;
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global using Microsoft.Data.SqlClient;
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global using Microsoft.Data.SqlClient.Server;
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global using MySql.Data;
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global using MySql.Data.Types;
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global using MySql.Data.MySqlClient;
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global using Microsoft.Data.Sqlite;
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global using DuckDB.NET.Data;
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global using DuckDB.NET.Data.DataChunk;
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global using Dapper;
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global using Npgsql;
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global using Npgsql.Schema;
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global using Npgsql.PostgresTypes;
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global using Npgsql.TypeMapping;
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global using Npgsql.Util;
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global using Npgsql.NameTranslation;
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global using Npgsql.BackendMessages;
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global using Microsoft.EntityFrameworkCore;
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global using Microsoft.EntityFrameworkCore.SqlServer;
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global using Microsoft.EntityFrameworkCore.Sqlite;
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global using Npgsql.EntityFrameworkCore.PostgreSQL;
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global using MySql.EntityFrameworkCore;
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global using MongoDB.EntityFrameworkCore;
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//共享方法
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public static List<Student> DatatableToStudent(DataTable studentTable)
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{
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var students = new List<Student>();
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if(studentTable == null)
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{
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return students;
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}
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if(studentTable.Columns.Count ==0)
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{
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return students;
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}
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if(studentTable.Rows.Count <=0)
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{
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return students;
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}
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foreach(DataRow row in studentTable.Rows)
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{
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var student = new Student()
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{
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Id = (int)row["Id"],
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Name = row["Name"] == DBNull.Value ? "" : (string)row["Name"].ToString(),
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Age = row["Age"] == DBNull.Value ? 0 : (int)row["Age"]
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};
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students.Add(student);
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}
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return students;
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}
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```
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## 使用 ADO.NET
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### SQL Server 数据库(2019为例)
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```csharp
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//Ado.Net 操作SQL Server
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{
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DataSet ds = new DataSet();
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using(var mssqlConnection = new SqlConnection(SharedDbConnect.MsSqlConnectionString))
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{
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mssqlConnection.Open();
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var querySql = "select * FROM student where age >@age;";
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SqlParameter[] parameters = new SqlParameter[]
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{
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new SqlParameter()
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{
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ParameterName = "age",
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SqlDbType = SqlDbType.Int,
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Value = 50,
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Direction = ParameterDirection.Input,
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Size = 4,
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DbType = DbType.Int32,
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IsNullable = false,
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}
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};
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var command = new SqlCommand(querySql, mssqlConnection);
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command.Parameters.AddRange(parameters);
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var adapter = new SqlDataAdapter(command);
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adapter.Fill(ds);
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mssqlConnection.Close();
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mssqlConnection.Dispose();
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}
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var students = DatatableToStudent(ds.Tables[0]);
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Console.WriteLine($"查询到: {students.Count()} 行数据");
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var jsonText = System.Text.Json.JsonSerializer.Serialize(students.Take<Student>(2), new System.Text.Json.JsonSerializerOptions()
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{
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Encoder = System.Text.Encodings.Web.JavaScriptEncoder.Create(System.Text.Unicode.UnicodeRanges.All),
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WriteIndented = false,
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});
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Console.WriteLine($"前2行：{jsonText}");
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}
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```
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### MySQL
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```csharp
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//Ado.Net 操作MySQL
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{
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//查询数据
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DataSet ds = new DataSet();
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using(var sqlConnection = new MySqlConnection(SharedDbConnect.MySQLConnectionString))
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{
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sqlConnection.Open();
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var querySql = "SELECT * FROM `Student` LIMIT 2;";
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var command = new MySqlCommand(querySql, sqlConnection);
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var adapter = new MySqlDataAdapter(command);
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adapter.Fill(ds);
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sqlConnection.Close();
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sqlConnection.Dispose();
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}
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//输出数据
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var dt = ds.Tables[0];
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int padRightCount = 15;
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//输出列
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List<string> columnNames = new List<string>(100);
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foreach(DataColumn c in dt.Columns)
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{
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columnNames.Add(c.ColumnName.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("", columnNames));
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//输出数据
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foreach(DataRow row in dt.Rows)
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{
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List<string> rowItemValues = new List<string>(100);
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for(int i=0; i<columnNames.Count(); i++)
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{
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var valueText = row[i] == DBNull.Value? "null" : row[i].ToString();
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rowItemValues.Add(valueText.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("",rowItemValues));
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}
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}
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```
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### PostgreSQL
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```csharp
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//Ado.Net 操作PostgreSQL
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{
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//查询数据
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DataSet ds = new DataSet();
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using(var sqlConnection = new NpgsqlConnection(SharedDbConnect.PSQLConnectionString))
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{
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sqlConnection.Open();
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var querySql =
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"""
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SELECT * FROM "Student" LIMIT 5;
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""";
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var command = new NpgsqlCommand(querySql, sqlConnection);
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var adapter = new NpgsqlDataAdapter(command);
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adapter.Fill(ds);
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sqlConnection.Close();
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sqlConnection.Dispose();
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}
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//输出数据
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var dt = ds.Tables[0];
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int padRightCount = 15;
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//输出列
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List<string> columnNames = new List<string>(100);
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foreach(DataColumn c in dt.Columns)
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{
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columnNames.Add(c.ColumnName.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("", columnNames));
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//输出数据
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foreach(DataRow row in dt.Rows)
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{
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List<string> rowItemValues = new List<string>(100);
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for(int i=0; i<columnNames.Count(); i++)
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{
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var valueText = row[i] == DBNull.Value? "null" : row[i].ToString();
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rowItemValues.Add(valueText.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("",rowItemValues));
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}
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}
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```
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```csharp
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//Ado.Net 操作PostgreSQL: 客户端官方用法(异步)
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{
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//查询数据
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DataSet ds = new DataSet();
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int padRightCount = 15;
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await using var dataSource = NpgsqlDataSource.Create(SharedDbConnect.PSQLConnectionString);
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await using (var cmd = dataSource.CreateCommand("SELECT * FROM \"Student\" LIMIT 5;"))
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await using (var reader = await cmd.ExecuteReaderAsync())
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{
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//输出列名
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List<string> columnNames = reader.GetColumnSchema().Select(c => c.ColumnName.PadRight(padRightCount)).ToList();
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Console.WriteLine(string.Join("", columnNames));
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//循环输出行数据
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while (await reader.ReadAsync())
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{
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List<string> rowItemValues = new List<string>(100);
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for(int i=0; i<columnNames.Count(); i++)
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{
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var valueText = reader.GetFieldValue<object>(i).ToString();
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rowItemValues.Add(valueText.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("",rowItemValues));
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}
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}
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}
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```
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### SQLite
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```csharp
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//Ado.Net 操作SQLite
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{
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//查询数据
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DataSet ds = new DataSet();
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int padRightCount = 15;
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using(var sqlConnection = new SqliteConnection(SharedDbConnect.SQLiteConnectionString))
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{
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sqlConnection.Open();
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var querySql =
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"""
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SELECT * FROM Student LIMIT 5;
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""";
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var cmd = sqlConnection.CreateCommand();
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cmd.CommandType = CommandType.Text;
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cmd.CommandText = querySql;
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using (var reader = await cmd.ExecuteReaderAsync())
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{
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//输出列名
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List<string> columnNames = reader.GetColumnSchema().Select(c => c.ColumnName.PadRight(padRightCount)).ToList();
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Console.WriteLine(string.Join("", columnNames));
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//循环输出行数据
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while (await reader.ReadAsync())
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{
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List<string> rowItemValues = new List<string>(100);
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for(int i=0; i<columnNames.Count(); i++)
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{
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var valueText = reader.GetFieldValue<object>(i).ToString();
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rowItemValues.Add(valueText.PadRight(padRightCount));
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}
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Console.WriteLine(string.Join("",rowItemValues));
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}
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}
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sqlConnection.Close();
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sqlConnection.Dispose();
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}
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}
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```
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### DuckDB
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```csharp
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//Ado.Net 操作DuckDB数据库
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{
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int padRightCount = 15;
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using(var sqlConnection = new DuckDBConnection(SharedDbConnect.DuckDBConnectionString))
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{
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sqlConnection.Open();
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//1、创建表
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var createTableSql =
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"""
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CREATE TABLE Student
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(
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Id INTEGER,
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Name TEXT,
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Age INTEGER
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);
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""";
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var createCommand = sqlConnection.CreateCommand();
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createCommand.CommandType = CommandType.Text;
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createCommand.CommandText = createTableSql;
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var createCount = createCommand.ExecuteNonQuery();
|
|
|
|
|
//Console.WriteLine($"{createCount}");
|
|
|
|
|
|
|
|
|
|
//2、插入示例数据
|
|
|
|
|
var insertSql =
|
|
|
|
|
"""
|
|
|
|
|
INSERT INTO Student VALUES (1, '张三', 10), (2, '李四', 33), (3, '王五', 66);
|
|
|
|
|
""";
|
|
|
|
|
|
|
|
|
|
var insertCommand = sqlConnection.CreateCommand();
|
|
|
|
|
insertCommand.CommandType = CommandType.Text;
|
|
|
|
|
insertCommand.CommandText = insertSql;
|
|
|
|
|
|
|
|
|
|
var insertCount = insertCommand.ExecuteNonQuery();
|
|
|
|
|
//Console.WriteLine($"{insertCount}");
|
|
|
|
|
|
|
|
|
|
//3、查询数据
|
|
|
|
|
var querySql =
|
|
|
|
|
"""
|
|
|
|
|
SELECT * FROM Student ORDER BY Age
|
|
|
|
|
""";
|
|
|
|
|
var queryCommand = sqlConnection.CreateCommand();
|
|
|
|
|
queryCommand.CommandType = CommandType.Text;
|
|
|
|
|
queryCommand.CommandText = querySql;
|
|
|
|
|
|
|
|
|
|
using (var reader = await queryCommand.ExecuteReaderAsync())
|
|
|
|
|
{
|
|
|
|
|
//输出列名
|
|
|
|
|
List<string> columnNames = reader.GetColumnSchema().Select(c => c.ColumnName.PadRight(padRightCount)).ToList();
|
|
|
|
|
Console.WriteLine(string.Join("", columnNames));
|
|
|
|
|
|
|
|
|
|
//循环输出行数据
|
|
|
|
|
while (await reader.ReadAsync())
|
|
|
|
|
{
|
|
|
|
|
List<string> rowItemValues = new List<string>(100);
|
|
|
|
|
for(int i=0; i<columnNames.Count(); i++)
|
|
|
|
|
{
|
|
|
|
|
var valueText = reader.GetValue(i).ToString();
|
|
|
|
|
rowItemValues.Add(valueText.PadRight(padRightCount));
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
Console.WriteLine(string.Join("",rowItemValues));
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
sqlConnection.Close();
|
|
|
|
|
sqlConnection.Dispose();
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
## 使用 Dapper
|
|
|
|
|
### Dapper 操作 SQL Server 2019
|
|
|
|
|
```csharp
|
|
|
|
|
//Dapper 操作SQL Server
|
|
|
|
|
{
|
|
|
|
|
using(var mssqlConnection = new SqlConnection(SharedDbConnect.MsSqlConnectionString))
|
|
|
|
|
{
|
|
|
|
|
var querySql = "select * FROM student;";
|
|
|
|
|
var students = mssqlConnection.Query<Student>(querySql).Take(2);
|
|
|
|
|
var jsonText = System.Text.Json.JsonSerializer.Serialize(students, new System.Text.Json.JsonSerializerOptions()
|
|
|
|
|
{
|
|
|
|
|
Encoder = System.Text.Encodings.Web.JavaScriptEncoder.Create(System.Text.Unicode.UnicodeRanges.All),
|
|
|
|
|
WriteIndented = false,
|
|
|
|
|
});
|
|
|
|
|
|
|
|
|
|
Console.WriteLine(jsonText);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
### Dapper 操作 MySQL
|
|
|
|
|
```csharp
|
|
|
|
|
//Dapper 操作MySQL
|
|
|
|
|
{
|
|
|
|
|
using(var dbConnection = new MySqlConnection(SharedDbConnect.MySQLConnectionString))
|
|
|
|
|
{
|
|
|
|
|
var querySql = "SELECT * FROM `Student` LIMIT @top;";
|
|
|
|
|
var students = dbConnection.Query<Student>(querySql, new {top=2});
|
|
|
|
|
|
|
|
|
|
var jsonText = System.Text.Json.JsonSerializer.Serialize(students, new System.Text.Json.JsonSerializerOptions()
|
|
|
|
|
{
|
|
|
|
|
Encoder = System.Text.Encodings.Web.JavaScriptEncoder.Create(System.Text.Unicode.UnicodeRanges.All),
|
|
|
|
|
WriteIndented = false,
|
|
|
|
|
});
|
|
|
|
|
|
|
|
|
|
Console.WriteLine(jsonText);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
### Dapper 操作 PostgreSQL
|
|
|
|
|
```csharp
|
|
|
|
|
//Dapper 操作 PSQL
|
|
|
|
|
{
|
|
|
|
|
using(var dbConnection = new NpgsqlConnection(SharedDbConnect.PSQLConnectionString))
|
|
|
|
|
{
|
|
|
|
|
var querySql = "SELECT * FROM \"Student\" Where \"Age\" > @Age LIMIT @Top;";
|
|
|
|
|
var students = dbConnection.Query<Student>(querySql, new {Age = 50, top = 2});
|
|
|
|
|
|
|
|
|
|
var jsonText = System.Text.Json.JsonSerializer.Serialize(students, new System.Text.Json.JsonSerializerOptions()
|
|
|
|
|
{
|
|
|
|
|
Encoder = System.Text.Encodings.Web.JavaScriptEncoder.Create(System.Text.Unicode.UnicodeRanges.All),
|
|
|
|
|
WriteIndented = false,
|
|
|
|
|
});
|
|
|
|
|
|
|
|
|
|
Console.WriteLine(jsonText);
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
## 使用 EF Core
|
|
|
|
|
```csharp
|
|
|
|
|
//共享
|
|
|
|
|
/// <summary>
|
|
|
|
|
/// SQL Server DbContext
|
|
|
|
|
/// </summary>
|
|
|
|
|
public class StudyDbContext: DbContext
|
|
|
|
|
{
|
|
|
|
|
public StudyDbContext(DbContextOptions<StudyDbContext> option):base(option)
|
|
|
|
|
{
|
|
|
|
|
|
|
|
|
|
}
|
|
|
|
|
|
|
|
|
|
public DbSet<Student> Student {get; set;}
|
|
|
|
|
|
|
|
|
|
protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
|
|
|
|
|
{
|
|
|
|
|
base.OnConfiguring(optionsBuilder);
|
|
|
|
|
if(!optionsBuilder.IsConfigured)
|
|
|
|
|
{
|
|
|
|
|
Console.WriteLine("没有设置");
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
### EF Core 操作 SQL Server
|
|
|
|
|
|
|
|
|
|
```csharp
|
|
|
|
|
{ //EF Core SQL Server
|
|
|
|
|
var builder = new DbContextOptionsBuilder<StudyDbContext>();
|
|
|
|
|
builder.UseSqlServer(SharedDbConnect.MsSqlConnectionString);
|
|
|
|
|
|
|
|
|
|
var dbContext = new StudyDbContext(builder.Options);
|
|
|
|
|
var students = dbContext.Student.Where(s => s.Age> 95).ToList();
|
|
|
|
|
students.Display();
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
### EF Core 查询 MySQL
|
|
|
|
|
```csharp
|
|
|
|
|
{ //EF Core MySQL
|
|
|
|
|
var builder = new DbContextOptionsBuilder<StudyDbContext>();
|
|
|
|
|
builder.UseMySQL(SharedDbConnect.MySQLConnectionString);
|
|
|
|
|
|
|
|
|
|
var dbContext = new StudyDbContext(builder.Options);
|
|
|
|
|
var students = dbContext.Student.Where(s => s.Age> 95).ToList();
|
|
|
|
|
students.Display();
|
|
|
|
|
}
|
|
|
|
|
```
|
|
|
|
|
### EFCore PostgreSQL
|
|
|
|
|
```csharp
|
|
|
|
|
{
|
|
|
|
|
var builder = new DbContextOptionsBuilder<StudyDbContext>();
|
|
|
|
|
builder.UseNpgsql(SharedDbConnect.PSQLConnectionString);
|
|
|
|
|
|
|
|
|
|
var dbContext = new StudyDbContext(builder.Options);
|
|
|
|
|
var students = dbContext.Student.Where(s => s.Age> 95).ToList();
|
|
|
|
|
students.Display();
|
|
|
|
|
}
|
|
|
|
|
```
|
