public override Expression VisitTable(TableExpression tableExpression)
{
var exp = tableExpression;
var versionedQuerySettings = VersionedQuerySettings.Current;
if (versionedQuerySettings != null && versionedQuerySettings.SystemVersionEnabled && versionedQuerySettings.IsTableVersioned(exp.Schema, exp.Table))
{
var identifier = VersionedQuerySettings.ConvertToVersionedIdentifier(exp.Table);
tableExpression = new TableExpression(identifier, tableExpression.Schema, tableExpression.Alias, tableExpression.QuerySource);
}
return(base.VisitTable(tableExpression));
}
public TemporalQueryContext(DbContext dbContext, TemporalQuery queryClause, ILogger logger = null)
{
this.dbContext = dbContext;
this.queryClause = queryClause;
this.logger = logger;
previousSettings = VersionedQuerySettings.Current;
var forClause = queryClause.GetClause();
if (string.IsNullOrEmpty(forClause))
{
VersionedQuerySettings.Current = null;
}
else
{
VersionedQuerySettings.Current = new VersionedQuerySettings
{
SystemVersionEnabled = true,
ForClause = forClause,
VersionedTables = GetVersionedTablesFromDbConetxt(dbContext, logger)
};
}
}
public override void DelimitIdentifier(StringBuilder builder, string identifier)
{
string versionedTable = null;
var versionedQuerySettings = VersionedQuerySettings.Current;
if (versionedQuerySettings != null && versionedQuerySettings.SystemVersionEnabled && VersionedQuerySettings.ParseVersionedIdentifier(identifier, out versionedTable))
{
identifier = versionedTable;
}
base.DelimitIdentifier(builder, identifier);
if (versionedTable != null)
{
builder.Append(versionedQuerySettings.ForClause);
}
}
public override string DelimitIdentifier(string identifier)
{
string versionedTable = null;
var versionedQuerySettings = VersionedQuerySettings.Current;
if (versionedQuerySettings != null && versionedQuerySettings.SystemVersionEnabled && VersionedQuerySettings.ParseVersionedIdentifier(identifier, out versionedTable))
{
identifier = versionedTable;
}
var str = base.DelimitIdentifier(identifier);
return(versionedTable != null ? str + versionedQuerySettings.ForClause : str);
}
