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sqlpp11/docs/Insert.md
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add Dynamic-Insert.md (#413)
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Introduction

This page explains insert statements with a static structure. If you want to learn about constructing insert statements at runtime, you should still read this page first and then move on to dynamic insert statements.

A Basic example

Haven't found the time to document this in any detail, yet, but this is an example:

db(insert_into(tab).set(tab.gamma = true));
db(insert_into(tabDateTime)
      .set(tabDateTime.colTimePoint = std::chrono::system_clock::now()));

This is how you could insert multiple rows at a time:

auto multi_insert = insert_into(t).columns(t.gamma, t.beta, t.delta);
multi_insert.values.add(t.gamma = true, t.beta = "cheesecake", t.delta = 1);
multi_insert.values.add(t.gamma = sqlpp::default_value, t.beta = sqlpp::default_value,
                        t.delta = sqlpp::default_value);
multi_insert.values.add(t.gamma = sqlpp::value_or_null(true),
                        t.beta = sqlpp::value_or_null("pie"),
                        t.delta = sqlpp::value_or_null<sqlpp::integer>(sqlpp::null));
db(multi_insert);

Note that add currently requires precise value types, equal to the respective column's value type. For instance, time point columns are represented as std::chrono::time_point<std::chrono::system_clock, std::chrono::microseconds>.

Thus, when using such a column in a multi_insert, you might have to cast to the right time point.

  auto multi_time_insert = insert_into(tabDateTime).columns(tabDateTime.colTimePoint);
  multi_time_insert.values.add(tabDateTime.colTimePoint = std::chrono::time_point_cast<std::chrono::microseconds>(
                                   std::chrono::system_clock::now()));

Similar for other data types.

See also dynamic insert statements.