/// <summary>
/// 更新实例。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Update(IEntityType entityType)
{
var entry = _updates.GetOrAdd(entityType.ClrType, key =>
{
var names = entityType.GetProperties()
.Where(property => property.IsUpdatable())
.Select(property => property.Name)
.ToList();
var builder = new SqlIndentedStringBuilder();
builder.Append("UPDATE ").Append(SqlHelper.DelimitIdentifier(entityType.Table)).Append(" SET ");
builder.JoinAppend(names.Select(name => $"{SqlHelper.DelimitIdentifier(name)}={SqlHelper.Parameterized(name)}")).AppendLine();
if (entityType.PrimaryKey != null)
{
var primaryKeys = entityType.PrimaryKey.Properties
.Select(p => p.Name)
.ToList();
builder.Append("WHERE ")
.JoinAppend(
primaryKeys.Select(
name => $"{SqlHelper.DelimitIdentifier(name)}={SqlHelper.Parameterized(name)}"), " AND ")
.Append(SqlHelper.StatementTerminator);
names.AddRange(primaryKeys);
}
return(new CacheEntry(builder.ToString(), names));
});
return(new SqlIndentedStringBuilder(entry.Sql, entry.Parameters));
}
/// <summary>
/// 更新实例。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="expression">条件表达式。</param>
/// <param name="parameters">匿名对象。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Update(IEntityType entityType, Expression expression, LambdaExpression parameters)
{
var builder = new SqlIndentedStringBuilder();
builder.Append("UPDATE ").Append(SqlHelper.DelimitIdentifier(entityType.Table)).Append(" SET ");
builder.Append(VisitUpdateExpression(parameters));
builder.AppendEx(Visit(expression), " WHERE {0}").Append(SqlHelper.StatementTerminator);
return(builder);
}
/// <summary>
/// 判断是否存在。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="expression">条件表达式。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Any(IEntityType entityType, Expression expression)
{
var builder = new SqlIndentedStringBuilder();
builder.Append("SELECT 1 FROM ").Append(SqlHelper.DelimitIdentifier(entityType.Table));
builder.AppendEx(Visit(expression), " WHERE {0}").Append(SqlHelper.StatementTerminator);
return(builder);
}
/// <summary>
/// 判断唯一主键关联是否存在。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Any(IEntityType entityType)
{
var builder = new SqlIndentedStringBuilder();
builder.Append("SELECT 1 FROM ").Append(SqlHelper.DelimitIdentifier(entityType.Table));
AppendWherePrimaryKey(builder, entityType);
return(builder);
}
/// <summary>
/// 将唯一主键附加到当前语句构建实例中。
/// </summary>
/// <param name="builder">SQL语句构建实例。</param>
/// <param name="entityType">当前实体类。</param>
/// <param name="terminated">是否结束语句。</param>
protected void AppendWherePrimaryKey(SqlIndentedStringBuilder builder, IEntityType entityType, bool terminated = true)
{
var primaryKey = SqlHelper.DelimitIdentifier(entityType.SingleKey().Name);
builder.Append($" WHERE {primaryKey} = {PrimaryKeyParameter}");
if (terminated)
{
builder.AppendLine(SqlHelper.StatementTerminator);
}
}
/// <summary>
/// 快速构建唯一主键SQL语句。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="sqlHeader">SQL语句头，如：DELETE FROM等。</param>
/// <param name="key">主键值。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder PrimaryKeySql(IEntityType entityType, string sqlHeader, object key)
{
var builder = new SqlIndentedStringBuilder();
builder.Append(sqlHeader).Append(" ")
.Append(SqlHelper.DelimitIdentifier(entityType.Table));
AppendWherePrimaryKey(builder, entityType);
builder.AddPrimaryKey(key);
return(builder);
}
/// <summary>
/// 更新实例。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="expression">条件表达式。</param>
/// <param name="parameters">匿名对象。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Update(IEntityType entityType, Expression expression, object parameters)
{
var builder = new SqlIndentedStringBuilder();
builder.Append("UPDATE ").Append(SqlHelper.DelimitIdentifier(entityType.Table)).Append(" SET ");
builder.CreateObjectParameters(parameters);
builder.JoinAppend(builder.Parameters.Keys.Select(
name => $"{SqlHelper.DelimitIdentifier(name)}={SqlHelper.Parameterized(name)}"));
builder.AppendEx(Visit(expression), " WHERE {0}").Append(SqlHelper.StatementTerminator);
return(builder);
}
/// <summary>
/// 通过唯一主键更新实例。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="parameters">匿名对象。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Update(IEntityType entityType, object parameters)
{
var builder = new SqlIndentedStringBuilder();
builder.Append("UPDATE ").Append(SqlHelper.DelimitIdentifier(entityType.Table)).Append(" SET ");
builder.CreateObjectParameters(parameters);
builder.JoinAppend(builder.Parameters.Keys.Select(
name => $"{SqlHelper.DelimitIdentifier(name)}={SqlHelper.Parameterized(name)}"));
AppendWherePrimaryKey(builder, entityType);
return(builder);
}
/// <summary>
/// 聚合函数。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <param name="method">聚合函数。</param>
/// <param name="column">聚合列。</param>
/// <param name="expression">条件表达式。</param>
/// <param name="nullColumn">当<paramref name="column"/>为空的时候，使用的值。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Scalar(IEntityType entityType, string method, LambdaExpression column, Expression expression, string nullColumn = null)
{
if (column != null)
{
nullColumn = SqlHelper.DelimitIdentifier(column.GetPropertyAccess().Name);
}
var builder = new SqlIndentedStringBuilder();
builder.Append($"SELECT {method}({nullColumn}) FROM {SqlHelper.DelimitIdentifier(entityType.Table)}");
builder.AppendEx(Visit(expression), " WHERE {0}")
.AppendLine(SqlHelper.StatementTerminator);
return(builder);
}
/// <summary>
/// 新建实例。
/// </summary>
/// <param name="entityType">模型实例。</param>
/// <returns>返回SQL构建实例。</returns>
public virtual SqlIndentedStringBuilder Create(IEntityType entityType)
{
var entry = _creations.GetOrAdd(entityType.ClrType, key =>
{
var names = entityType.GetProperties()
.Where(property => property.IsCreatable())
.Select(property => property.Name)
.ToList();
var builder = new SqlIndentedStringBuilder();
builder.Append("INSERT INTO");
builder.Append(" ").Append(SqlHelper.DelimitIdentifier(entityType.Table));
builder.Append("(").JoinAppend(names.Select(SqlHelper.DelimitIdentifier)).Append(")");
builder.Append("VALUES(")
.JoinAppend(names.Select(SqlHelper.Parameterized))
.Append(")").AppendLine(SqlHelper.StatementTerminator);
if (entityType.Identity != null)
{
builder.Append(SelectIdentity());
}
return(new CacheEntry(builder.ToString(), names));
});
return(new SqlIndentedStringBuilder(entry.Sql, entry.Parameters));
}