// Before every execution, we must clear statement context.
func resetStmtCtx(ctx context.Context, s ast.StmtNode) {
sessVars := ctx.GetSessionVars()
sc := new(variable.StatementContext)
switch s.(type) {
case *ast.UpdateStmt, *ast.InsertStmt, *ast.DeleteStmt:
sc.IgnoreTruncate = false
sc.TruncateAsWarning = !sessVars.StrictSQLMode
if _, ok := s.(*ast.UpdateStmt); ok {
sc.InUpdateStmt = true
}
default:
sc.IgnoreTruncate = true
if show, ok := s.(*ast.ShowStmt); ok {
if show.Tp == ast.ShowWarnings {
sc.SetWarnings(sessVars.StmtCtx.GetWarnings())
}
}
}
sessVars.StmtCtx = sc
}
// FlagsToStatementContext creates a StatementContext from a `tipb.SelectRequest.Flags`.
func FlagsToStatementContext(flags uint64) *variable.StatementContext {
sc := new(variable.StatementContext)
sc.IgnoreTruncate = (flags & FlagIgnoreTruncate) > 0
sc.TruncateAsWarning = (flags & FlagTruncateAsWarning) > 0
return sc
}