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Npgsql Integration with Entity Framework Code First

I have a project using the latest version of EF CF with PostgreSQL and Npgsql.

My model looks like this:

[Table("mytable")]
public class MyTable
{
    [Column("id")]
    public int Id { get; set; }
    [Column("mycolumn")]
    public string MyColumn { get; set; }
}

And the database / tables / columns have lowercase names, for example:

CREATE TABLE mytable
{
    id serial,
    mycolumn character(50)
}

Npgsql generates SQL commands with quotes, so I have to use data annotations due to the characteristics of PostgreSQL, which is annoying. However, I would not want to use delimited quotes in the database.

Is there a way to configure Npgsql so that they do not include quotation marks when generating commands or force lowercase table / column names in generated SQL?

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2 answers

If I am not missing something, do you need a general way of changing the naming convention for tables?

EF6 custom conventions - , , ...

http://entityframework.codeplex.com/wikipage?title=Custom%20Conventions

/ Type, - . ( )...

1) IConfigurationConvention<Type, EntityTypeConfiguration> ( EF EntityConventionBase)

2) Apply - , (ToTable()) - - .ToLowerCase()

3) ...

...

public class SmallCapsEntitiesConfigurationConvention
    : IConfigurationConvention<Type, EntityTypeConfiguration>
{
    public void Apply(Type memberInfo, Func<EntityTypeConfiguration> configuration)
    {
        configuration().ToTable(memberInfo.Name.ToLowerInvariant(), null);
    }
}


http://blog.cincura.net/233167-custom-conventions-in-entity-framework-6-helping-firebird/

, Npgsql/PostgreSQL - "". EF.

+8

EF Core.

tables, properties, keys indexes Postgre, :

using System;
using System.Text.RegularExpressions;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Metadata;
using Npgsql;

namespace Database.Customization
{
    public class PostgreDbContext : DbContext
    {
        private static readonly Regex _keysRegex = new Regex("^(PK|FK|IX)_", RegexOptions.Compiled);

        public PostgreDbContext(DbContextOptions options)
            : base(options)
        {
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);
            FixSnakeCaseNames(modelBuilder);
        }

        private void FixSnakeCaseNames(ModelBuilder modelBuilder)
        {
            var mapper = new NpgsqlSnakeCaseNameTranslator();
            foreach (var table in modelBuilder.Model.GetEntityTypes())
            {
                ConvertToSnake(mapper, table);
                foreach (var property in table.GetProperties())
                {
                    ConvertToSnake(mapper, property);
                }

                foreach (var primaryKey in table.GetKeys())
                {
                    ConvertToSnake(mapper, primaryKey);
                }

                foreach (var foreignKey in table.GetForeignKeys())
                {
                    ConvertToSnake(mapper, foreignKey);
                }

                foreach (var indexKey in table.GetIndexes())
                {
                    ConvertToSnake(mapper, indexKey);
                }
            }
        }

        private void ConvertToSnake(INpgsqlNameTranslator mapper, object entity)
        {
            switch (entity)
            {
                case IMutableEntityType table:
                    var relationalTable = table.Relational();
                    relationalTable.TableName = ConvertGeneralToSnake(mapper, relationalTable.TableName);
                    if (relationalTable.TableName.StartsWith("asp_net_"))
                    {
                        relationalTable.TableName = relationalTable.TableName.Replace("asp_net_", string.Empty);
                        relationalTable.Schema = "identity";
                    }

                    break;
                case IMutableProperty property:
                    property.Relational().ColumnName = ConvertGeneralToSnake(mapper, property.Relational().ColumnName);
                    break;
                case IMutableKey primaryKey:
                    primaryKey.Relational().Name = ConvertKeyToSnake(mapper, primaryKey.Relational().Name);
                    break;
                case IMutableForeignKey foreignKey:
                    foreignKey.Relational().Name = ConvertKeyToSnake(mapper, foreignKey.Relational().Name);
                    break;
                case IMutableIndex indexKey:
                    indexKey.Relational().Name = ConvertKeyToSnake(mapper, indexKey.Relational().Name);
                    break;
                default:
                    throw new NotImplementedException("Unexpected type was provided to snake case converter");
            }
        }

        private string ConvertKeyToSnake(INpgsqlNameTranslator mapper, string keyName) =>
            ConvertGeneralToSnake(mapper, _keysRegex.Replace(keyName, match => match.Value.ToLower()));

        private string ConvertGeneralToSnake(INpgsqlNameTranslator mapper, string entityName) =>
            mapper.TranslateMemberName(ModifyNameBeforeConvertion(mapper, entityName));

        protected virtual string ModifyNameBeforeConvertion(INpgsqlNameTranslator mapper, string entityName) => entityName;
    }
}
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