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Diffstat (limited to 'odb/odb/relational/mysql/schema.cxx')
| -rw-r--r-- | odb/odb/relational/mysql/schema.cxx | 489 |
1 files changed, 489 insertions, 0 deletions
diff --git a/odb/odb/relational/mysql/schema.cxx b/odb/odb/relational/mysql/schema.cxx new file mode 100644 index 0000000..60dc95b --- /dev/null +++ b/odb/odb/relational/mysql/schema.cxx @@ -0,0 +1,489 @@ +// file : odb/relational/mysql/schema.cxx +// license : GNU GPL v3; see accompanying LICENSE file + +#include <odb/relational/schema.hxx> + +#include <odb/relational/mysql/common.hxx> +#include <odb/relational/mysql/context.hxx> + +using namespace std; + +namespace relational +{ + namespace mysql + { + namespace schema + { + namespace relational = relational::schema; + using relational::table_set; + + // + // Drop. + // + + struct drop_foreign_key: relational::drop_foreign_key, context + { + drop_foreign_key (base const& x): base (x) {} + + virtual void + drop (sema_rel::table& t, sema_rel::foreign_key& fk) + { + /* + // @@ This does not work: in MySQL control statements can only + // be used in stored procedures. It seems the only way to + // implement this is to define, execute, and drop a stored + // procedure, which is just too ugly. + // + // Another option would be to use CREATE TABLE IF NOT EXISTS + // to create a dummy table with a dummy constraint that makes + // the following DROP succeed. Note, however, that MySQL issues + // a notice if the table already exist so would need to suppress + // that as well. Still not sure that the utility of this support + // justifies this kind of a hack. + // + os << "IF EXISTS (SELECT NULL FROM information_schema.TABLE_CONSTRAINTS" << endl + << " WHERE CONSTRAINT_TYPE = " << quote_string ("FOREIGN KEY") << "AND" << endl + << " CONSTRAINT_SCHEMA = DATABASE() AND" << endl + << " CONSTRAINT_NAME = " << quote_string (fk.name ()) << ") THEN" << endl + << " ALTER TABLE " << quote_id (t.name ()) << " DROP FOREIGN KEY " << quote_id (fk.name ()) << ";" << endl + << "END IF;" << endl; + */ + + // So for now we only do this in migration. + // + if (dropped_ == 0) + { + if (fk.not_deferrable ()) + pre_statement (); + else + { + if (format_ != schema_format::sql) + return; + + os << "/*" << endl; + } + + os << "ALTER TABLE " << quote_id (t.name ()) << endl + << " DROP FOREIGN KEY " << quote_id (fk.name ()) << endl; + + if (fk.not_deferrable ()) + post_statement (); + else + os << "*/" << endl + << endl; + } + } + + using base::drop; + + virtual void + traverse (sema_rel::drop_foreign_key& dfk) + { + // Find the foreign key we are dropping in the base model. + // + sema_rel::foreign_key& fk (find<sema_rel::foreign_key> (dfk)); + + if (fk.not_deferrable () || in_comment) + base::traverse (dfk); + else + { + if (format_ != schema_format::sql) + return; + + os << endl + << " /*" + << endl; + + drop (dfk); + + os << endl + << " */"; + } + } + + virtual void + drop_header () + { + os << "DROP FOREIGN KEY "; + } + }; + entry<drop_foreign_key> drop_foreign_key_; + + struct drop_index: relational::drop_index, context + { + drop_index (base const& x): base (x) {} + + virtual void + drop (sema_rel::index& in) + { + sema_rel::table& t (static_cast<sema_rel::table&> (in.scope ())); + + os << "DROP INDEX " << name (in) << " ON " << + quote_id (t.name ()) << endl; + } + }; + entry<drop_index> drop_index_; + + // + // Create. + // + + struct create_column: relational::create_column, context + { + create_column (base const& x): base (x) {} + + virtual void + auto_ (sema_rel::primary_key&) + { + os << " AUTO_INCREMENT"; + } + }; + entry<create_column> create_column_; + + struct create_foreign_key: relational::create_foreign_key, context + { + create_foreign_key (base const& x): base (x) {} + + void + diagnose (sema_rel::foreign_key& fk) + { + if (fk.on_delete () != sema_rel::foreign_key::no_action) + { + cerr << "warning: foreign key '" << fk.name () << "' has " << + "ON DELETE clause but is disabled in MySQL due to lack " + "of deferrable constraint support" << endl; + + cerr << "info: consider using non-deferrable foreign keys (" << + "--fkeys-deferrable-mode)" << endl; + } + } + + virtual void + traverse_create (sema_rel::foreign_key& fk) + { + // MySQL does not support deferrable constraint checking. Output + // such foreign keys as comments, for documentation, unless we + // are generating embedded schema. + // + if (fk.not_deferrable ()) + base::traverse_create (fk); + else + { + diagnose (fk); + + // Don't bloat C++ code with comment strings if we are + // generating embedded schema. + // + if (format_ != schema_format::sql) + return; + + os << endl + << " /*" << endl + << " CONSTRAINT "; + create (fk); + os << endl + << " */"; + } + } + + virtual void + traverse_add (sema_rel::foreign_key& fk) + { + if (fk.not_deferrable () || in_comment) + base::traverse_add (fk); + else + { + diagnose (fk); + + if (format_ != schema_format::sql) + return; + + os << endl + << " /*" + << endl; + + add (fk); + + os << endl + << " */"; + } + } + + virtual void + deferrable (sema_rel::deferrable) + { + // This will still be called to output the comment. + } + }; + entry<create_foreign_key> create_foreign_key_; + + struct create_index: relational::create_index, context + { + create_index (base const& x): base (x) {} + + virtual void + create (sema_rel::index& in) + { + os << "CREATE "; + + if (!in.type ().empty ()) + os << in.type () << ' '; + + os << "INDEX " << name (in); + + if (!in.method ().empty ()) + os << " USING " << in.method (); + + os << endl + << " ON " << table_name (in) << " ("; + + columns (in); + + os << ")" << endl; + + if (!in.options ().empty ()) + os << ' ' << in.options () << endl; + } + }; + entry<create_index> create_index_; + + struct create_table: relational::create_table, context + { + create_table (base const& x): base (x) {} + + // See if there are any undefined foreign keys that are not + // deferrable. + // + bool + check_undefined_fk_deferrable_only (sema_rel::table& t) + { + for (sema_rel::table::names_iterator i (t.names_begin ()); + i != t.names_end (); ++i) + { + using sema_rel::foreign_key; + + if (foreign_key* fk = dynamic_cast<foreign_key*> (&i->nameable ())) + { + if (!fk->count ("mysql-fk-defined") && + fk->not_deferrable ()) + return false; + } + } + return true; + } + + virtual void + traverse (sema_rel::table& t) + { + if (pass_ == 1) + base::traverse (t); + else + { + // Add undefined foreign keys. + // + if (check_undefined_fk (t)) + { + bool deferrable (check_undefined_fk_deferrable_only (t)); + + if (!deferrable || format_ == schema_format::sql) + { + if (deferrable) + { + os << "/*" << endl; + in_comment = true; + } + else + pre_statement (); + + os << "ALTER TABLE " << quote_id (t.name ()); + + instance<create_foreign_key> cfk (*this); + trav_rel::unames n (*cfk); + names (t, n); + os << endl; + + if (deferrable) + { + in_comment = false; + os << "*/" << endl + << endl; + } + else + post_statement (); + } + } + } + } + }; + entry<create_table> create_table_; + + // + // Alter. + // + + struct alter_column: relational::alter_column, context + { + alter_column (base const& x): base (x) {} + + virtual void + alter_header () + { + os << "MODIFY COLUMN "; + } + }; + entry<alter_column> alter_column_; + + struct alter_table_pre: relational::alter_table_pre, context + { + alter_table_pre (base const& x): base (x) {} + + // Check if we are only dropping deferrable foreign keys. + // + bool + check_drop_deferrable_only (sema_rel::alter_table& at) + { + if (check<sema_rel::add_column> (at) || + check_alter_column_null (at, true)) + return false; + + for (sema_rel::alter_table::names_iterator i (at.names_begin ()); + i != at.names_end (); ++i) + { + using sema_rel::foreign_key; + using sema_rel::drop_foreign_key; + + if (drop_foreign_key* dfk = + dynamic_cast<drop_foreign_key*> (&i->nameable ())) + { + foreign_key& fk (find<foreign_key> (*dfk)); + + if (fk.not_deferrable ()) + return false; + } + } + return true; + } + + virtual void + alter (sema_rel::alter_table& at) + { + if (check_drop_deferrable_only (at)) + { + if (format_ != schema_format::sql) + return; + + os << "/*" << endl; + in_comment = true; + + os << "ALTER TABLE " << quote_id (at.name ()); + instance<drop_foreign_key> dfk (*this); + trav_rel::unames n (*dfk); + names (at, n); + os << endl; + + in_comment = false; + os << "*/" << endl + << endl; + } + else + base::alter (at); + } + }; + entry<alter_table_pre> alter_table_pre_; + + struct alter_table_post: relational::alter_table_post, context + { + alter_table_post (base const& x): base (x) {} + + // Check if we are only adding deferrable foreign keys. + // + bool + check_add_deferrable_only (sema_rel::alter_table& at) + { + if (check<sema_rel::drop_column> (at) || + check_alter_column_null (at, false)) + return false; + + for (sema_rel::alter_table::names_iterator i (at.names_begin ()); + i != at.names_end (); ++i) + { + using sema_rel::add_foreign_key; + + if (add_foreign_key* afk = + dynamic_cast<add_foreign_key*> (&i->nameable ())) + { + if (afk->not_deferrable ()) + return false; + } + } + return true; + } + + virtual void + alter (sema_rel::alter_table& at) + { + if (check_add_deferrable_only (at)) + { + if (format_ != schema_format::sql) + return; + + os << "/*" << endl; + in_comment = true; + + os << "ALTER TABLE " << quote_id (at.name ()); + instance<create_foreign_key> cfk (*this); + trav_rel::unames n (*cfk); + names (at, n); + os << endl; + + in_comment = false; + os << "*/" << endl + << endl; + } + else + base::alter (at); + } + }; + entry<alter_table_post> alter_table_post_; + + // + // Schema version table. + // + + struct version_table: relational::version_table, context + { + version_table (base const& x): base (x) {} + + virtual void + create_table () + { + pre_statement (); + + os << "CREATE TABLE IF NOT EXISTS " << qt_ << " (" << endl + << " " << qn_ << " VARCHAR(128) NOT NULL PRIMARY KEY," << endl + << " " << qv_ << " BIGINT UNSIGNED NOT NULL," << endl + << " " << qm_ << " TINYINT(1) NOT NULL)" << endl; + + string const& engine (options.mysql_engine ()); + if (engine != "default") + os << " ENGINE=" << engine << endl; + + post_statement (); + } + + virtual void + create (sema_rel::version v) + { + pre_statement (); + + os << "INSERT IGNORE INTO " << qt_ << " (" << endl + << " " << qn_ << ", " << qv_ << ", " << qm_ << ")" << endl + << " VALUES (" << qs_ << ", " << v << ", 0)" << endl; + + post_statement (); + } + }; + entry<version_table> version_table_; + } + } +} |