#3: FK auto index

.github/workflows/build.yml

@@ -2,7 +2,7 @@ name: CI build
 on: 
   workflow_dispatch:
   push:
-    branches: master
+    branches: main
 jobs:
   build:
     runs-on: ubuntu-latest

core/src/main/java/io/github/mmm/orm/dialect/DbDialectStatementFormatter.java

@@ -12,7 +12,7 @@
 import io.github.mmm.orm.result.DbResultValue;
 import io.github.mmm.orm.statement.AbstractEntityClause;
 import io.github.mmm.orm.statement.BasicDbStatementFormatter;
-import io.github.mmm.orm.statement.select.SelectFrom;
+import io.github.mmm.orm.statement.select.SelectFromClause;
 import io.github.mmm.property.criteria.CriteriaFormatterFactory;
 
 /**
@@ -63,7 +63,7 @@ protected void formatEntityName(AbstractEntityClause<?, ?, ?> entityClause) {
   }
 
   @Override
-  protected void formatSelectAll(SelectFrom<?, ?> selectFrom) {
+  protected void formatSelectAll(SelectFromClause<?, ?> selectFrom) {
 
     EntityBean entity = selectFrom.getEntity();
     DbBeanMapper<EntityBean> mapping = this.dialect.getOrm().createBeanMapper(entity);

core/src/main/java/io/github/mmm/orm/naming/DbNamingStrategy.java

@@ -2,10 +2,14 @@
  * http://www.apache.org/licenses/LICENSE-2.0 */
 package io.github.mmm.orm.naming;
 
+import java.util.List;
+
 import io.github.mmm.base.text.CaseSyntax;
 import io.github.mmm.bean.BeanType;
 import io.github.mmm.entity.bean.EntityBean;
+import io.github.mmm.orm.ddl.DbColumnSpec;
 import io.github.mmm.orm.statement.AbstractEntityClause;
+import io.github.mmm.orm.statement.create.CreateIndexStatement;
 import io.github.mmm.property.ReadableProperty;
 import io.github.mmm.property.WritableProperty;
 import io.github.mmm.value.PropertyPath;
@@ -22,6 +26,29 @@
  */
 public interface DbNamingStrategy {
 
+  /**
+   * @return the maximum length for names of DDL elements (tables, columns, constraints, indexes, etc.) supported by the
+   *         underlying database. To avoid trouble you should name your entities and properties short but precise.
+   *         However, if you somehow exceed the limit, your names will be truncated automatically.
+   */
+  default int getMaximumNameLength() {
+
+    return 128;
+  }
+
+  /**
+   * @param name the suggested name of a DDL element.
+   * @return the given {@code name} clipped to ensure {@link #getMaximumNameLength()} is not exceeded.
+   */
+  default String clipName(String name) {
+
+    int max = getMaximumNameLength();
+    if (name.length() > max) {
+      return name.substring(0, max);
+    }
+    return name;
+  }
+
   /**
    * @param property the {@link ReadableProperty} to derive the column name from.
    * @return the column name for the given {@link ReadableProperty property}.
@@ -62,7 +89,7 @@ default String getColumnName(String columnName, PropertyPath<?> property) {
       builder.add(columnName);
       return builder.toString();
     }
-    return columnName;
+    return clipName(columnName);
   }
 
   /**
@@ -89,7 +116,8 @@ default String getColumnName(String rawColumnName, TypeMapper<?, ?> typeMapper)
     if ((suffix != null) && !suffix.isEmpty()) {
       suffix = getColumnName(suffix);
     }
-    return typeMapper.getNameMode().format(rawColumnName, suffix);
+    String columnName = typeMapper.getNameMode().format(rawColumnName, suffix);
+    return clipName(columnName);
   }
 
   /**
@@ -98,21 +126,21 @@ default String getColumnName(String rawColumnName, TypeMapper<?, ?> typeMapper)
    */
   default String getColumnName(String rawColumnName) {
 
-    return rawColumnName;
+    return clipName(rawColumnName);
   }
 
   /**
-   * @param bean the {@link EntityBean} to map to a database table.
+   * @param entity the {@link EntityBean} to map to a database table.
    * @return the physical table name.
    */
-  default String getTableName(EntityBean bean) {
+  default String getTableName(EntityBean entity) {
 
-    BeanType type = bean.getType();
+    BeanType type = entity.getType();
     String tableName = type.getMetaInfo().get(EntityBean.META_KEY_TABLE);
     if (tableName == null) {
       tableName = getTableName(type.getSimpleName());
     }
-    return tableName;
+    return clipName(tableName);
   }
 
   /**
@@ -135,7 +163,61 @@ default String getTableName(AbstractEntityClause<?, ?, ?> entityClause) {
    */
   default String getTableName(String rawTableName) {
 
-    return rawTableName;
+    return clipName(rawTableName);
+  }
+
+  /**
+   * @param createIndex the {@link CreateIndexStatement}.
+   * @return the static prefix for an {@link #getIndexName(CreateIndexStatement) index name}.
+   */
+  default String getIndexNamePrefix(CreateIndexStatement<?> createIndex) {
+
+    if (createIndex.getCreateIndex().isUnique()) {
+      return "UX";
+    } else {
+      return "IX";
+    }
+  }
+
+  /**
+   * @return the static infix for an {@link #getIndexName(CreateIndexStatement) index name} used to separate the
+   *         columns.
+   */
+  default String getIndexNameInfix() {
+
+    return "_";
+  }
+
+  /**
+   * @param createIndex the {@link CreateIndexStatement}.
+   * @return the auto-generated index name.
+   */
+  default String getIndexName(CreateIndexStatement<?> createIndex) {
+
+    EntityBean entity = createIndex.getOn().getEntity();
+    List<DbColumnSpec> columns = createIndex.getColumn().getColumns();
+    String tableName = getTableName(entity);
+    int capacity = 3 + tableName.length() + (columns.size() * 5);
+    int max = getMaximumNameLength();
+    if (capacity > max) {
+      capacity = max;
+    }
+    StringBuilder sb = new StringBuilder(capacity);
+    String infix = getIndexNameInfix();
+    sb.append(getIndexNamePrefix(createIndex));
+    sb.append(infix);
+    sb.append(tableName);
+    for (DbColumnSpec column : columns) {
+      column.getName();
+      String columnName = getColumnName(column.getProperty());
+      sb.append(infix);
+      sb.append(columnName);
+      if (sb.length() > max) {
+        break;
+      }
+    }
+    String indexName = sb.toString();
+    return clipName(indexName);
   }
 
   /**

core/src/main/java/io/github/mmm/orm/statement/AssignmentClause.java

@@ -10,7 +10,7 @@
 
 /**
  * {@link DbClause} containing {@link #getAssignments() assignments} like a
- * {@link io.github.mmm.orm.statement.insert.InsertValues}-clause.
+ * {@link io.github.mmm.orm.statement.insert.InsertValuesClause}-clause.
  *
  * @param <E> type of the {@link EntityBean} to query.
  * @param <SELF> type of this class itself.

core/src/main/java/io/github/mmm/orm/statement/BasicDbStatementFormatter.java

@@ -50,13 +50,13 @@
 import io.github.mmm.orm.statement.delete.DeleteClause;
 import io.github.mmm.orm.statement.impl.CriteriaJqlParametersInline;
 import io.github.mmm.orm.statement.insert.InsertClause;
-import io.github.mmm.orm.statement.insert.InsertValues;
+import io.github.mmm.orm.statement.insert.InsertValuesClause;
 import io.github.mmm.orm.statement.merge.MergeClause;
 import io.github.mmm.orm.statement.select.GroupByClause;
 import io.github.mmm.orm.statement.select.HavingClause;
 import io.github.mmm.orm.statement.select.OrderByClause;
 import io.github.mmm.orm.statement.select.SelectClause;
-import io.github.mmm.orm.statement.select.SelectFrom;
+import io.github.mmm.orm.statement.select.SelectFromClause;
 import io.github.mmm.orm.statement.select.SelectSequenceNextValueClause;
 import io.github.mmm.orm.statement.select.SelectStatement;
 import io.github.mmm.orm.statement.update.UpdateClause;
@@ -383,7 +383,7 @@ public void formatSelectClause(SelectClause<?> select, DbContext context) {
     writeIndent();
     write("SELECT ");
     SelectStatement<?> statement = select.getStatement();
-    SelectFrom<?, ?> selectFrom = null;
+    SelectFromClause<?, ?> selectFrom = null;
     if (statement != null) {
       selectFrom = statement.getFrom();
     }
@@ -505,9 +505,9 @@ public void formatAlterTableClause(AlterTableClause<?> alterTable, DbContext con
 
   /**
    * @param select the {@link SelectClause} with the {@link SelectClause#getSelections() selections}.
-   * @param selectFrom the {@link SelectFrom}.
+   * @param selectFrom the {@link SelectFromClause}.
    */
-  protected void formatSelections(SelectClause<?> select, SelectFrom<?, ?> selectFrom) {
+  protected void formatSelections(SelectClause<?> select, SelectFromClause<?, ?> selectFrom) {
 
     List<? extends CriteriaObject<?>> selectionCriterias = select.getSelections();
     if (selectionCriterias.isEmpty()) {
@@ -535,35 +535,39 @@ protected void formatSelections(SelectClause<?> select, SelectFrom<?, ?> selectF
   }
 
   /**
-   * @return {@code true} if a {@link SelectClause} of all properties should happen via {@link SelectFrom#getAlias()
-   *         alias}, {@code false} otherwise (to simply use {@code *}). The default is {@code false}. Override to
-   *         change. E.g. in JPQL you would write "SELECT a FROM Entity a ..." whereas in plain SQL you would write
-   *         "SELECT * FROM Entity ..."
+   * @return {@code true} if a {@link SelectClause} of all properties should happen via
+   *         {@link SelectFromClause#getAlias() alias}, {@code false} otherwise (to simply use {@code *}). The default
+   *         is {@code false}. Override to change. E.g. in JPQL you would write "SELECT a FROM Entity a ..." whereas in
+   *         plain SQL you would write "SELECT * FROM Entity ..."
    */
   public boolean isSelectAllByAlias() {
 
     return true;
   }
 
   /**
-   * @return {@code true} to use the {@code AS} keyword before an {@link SelectFrom#getAlias() alias} (e.g. "FROM Entity
-   *         <b>AS</b> e"), {@code false} otherwise.
+   * @return {@code true} to use the {@code AS} keyword before an {@link SelectFromClause#getAlias() alias} (e.g. "FROM
+   *         Entity <b>AS</b> e"), {@code false} otherwise.
    */
   public boolean isUseAsBeforeAlias() {
 
     return false;
   }
 
   /**
-   * @param selectFrom the {@link SelectFrom} giving access to the {@link SelectFrom#getAlias() alias}.
+   * @param selectFrom the {@link SelectFromClause} giving access to the {@link SelectFromClause#getAlias() alias}.
    */
-  protected void formatSelectAll(SelectFrom<?, ?> selectFrom) {
+  protected void formatSelectAll(SelectFromClause<?, ?> selectFrom) {
 
-    if (isSelectAllByAlias()) {
-      write(selectFrom.getAlias());
-      write(" ");
+    if (selectFrom == null) {
+      write("?"); // robustness to avoid toString fails in debugger while object is created.
     } else {
-      write("* ");
+      if (isSelectAllByAlias()) {
+        write(selectFrom.getAlias());
+        write(" ");
+      } else {
+        write("* ");
+      }
     }
   }
 
@@ -727,7 +731,7 @@ public void formatIntoClause(IntoClause<?, ?, ?> into, DbContext context) {
    */
   public void formatValuesClause(ValuesClause<?, ?> values, DbContext context) {
 
-    boolean isInto = values instanceof InsertValues;
+    boolean isInto = values instanceof InsertValuesClause;
     List<PropertyAssignment<?>> assignments = values.getAssignments();
     List<CriteriaObject<?>> args = null;
     if (isInto) {
@@ -1118,7 +1122,11 @@ public void formatCreateIndexClause(CreateIndexClause createIndex, DbContext con
       write("UNIQUE ");
     }
     write("INDEX ");
-    formatName(createIndex.getName());
+    String name = createIndex.getName();
+    if ((name == null) || name.isEmpty()) {
+      name = getOrm().getNamingStrategy().getIndexName(createIndex.getStatement());
+    }
+    formatName(name);
   }
 
   /**