| 1 | /* |
| 2 | |
| 3 | Derby - Class org.apache.derby.iapi.sql.dictionary.ConstraintDescriptor |
| 4 | |
| 5 | Copyright 1997, 2004 The Apache Software Foundation or its licensors, as applicable. |
| 6 | |
| 7 | Licensed under the Apache License, Version 2.0 (the "License"); |
| 8 | you may not use this file except in compliance with the License. |
| 9 | You may obtain a copy of the License at |
| 10 | |
| 11 | http://www.apache.org/licenses/LICENSE-2.0 |
| 12 | |
| 13 | Unless required by applicable law or agreed to in writing, software |
| 14 | distributed under the License is distributed on an "AS IS" BASIS, |
| 15 | WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| 16 | See the License for the specific language governing permissions and |
| 17 | limitations under the License. |
| 18 | |
| 19 | */ |
| 20 | |
| 21 | package org.apache.derby.iapi.sql.dictionary; |
| 22 | |
| 23 | import org.apache.derby.iapi.error.StandardException; |
| 24 | |
| 25 | import org.apache.derby.iapi.sql.depend.Provider; |
| 26 | import org.apache.derby.iapi.sql.depend.Dependent; |
| 27 | |
| 28 | import org.apache.derby.catalog.UUID; |
| 29 | |
| 30 | import org.apache.derby.iapi.reference.SQLState; |
| 31 | import org.apache.derby.iapi.services.sanity.SanityManager; |
| 32 | import org.apache.derby.iapi.sql.StatementType; |
| 33 | import org.apache.derby.catalog.DependableFinder; |
| 34 | import org.apache.derby.catalog.Dependable; |
| 35 | import org.apache.derby.iapi.services.io.StoredFormatIds; |
| 36 | import org.apache.derby.iapi.error.StandardException; |
| 37 | import org.apache.derby.iapi.sql.depend.DependencyManager; |
| 38 | import org.apache.derby.iapi.sql.depend.Dependent; |
| 39 | import org.apache.derby.iapi.sql.depend.Dependency; |
| 40 | import org.apache.derby.iapi.sql.depend.Provider; |
| 41 | import org.apache.derby.iapi.sql.conn.LanguageConnectionContext; |
| 42 | |
| 43 | /** |
| 44 | * This class is used to get information from a ConstraintDescriptor. |
| 45 | * A ConstraintDescriptor can represent a constraint on a table or on a |
| 46 | * column. |
| 47 | * |
| 48 | * @version 0.1 |
| 49 | * @author Jeff Lichtman |
| 50 | */ |
| 51 | |
| 52 | public abstract class ConstraintDescriptor |
| 53 | extends TupleDescriptor |
| 54 | implements UniqueTupleDescriptor, Provider, Dependent |
| 55 | { |
| 56 | // used to indicate what type of constraints we |
| 57 | // are interested in |
| 58 | public static final int ENABLED = 1; |
| 59 | public static final int DISABLED = 2; |
| 60 | public static final int ALL = 3; |
| 61 | |
| 62 | // field that we want users to be able to know about |
| 63 | public static final int SYSCONSTRAINTS_STATE_FIELD = 6; |
| 64 | |
| 65 | TableDescriptor table; |
| 66 | String constraintName; |
| 67 | boolean deferrable; |
| 68 | boolean initiallyDeferred; |
| 69 | boolean isEnabled; |
| 70 | int[] referencedColumns; |
| 71 | UUID constraintId; |
| 72 | SchemaDescriptor schemaDesc; |
| 73 | ColumnDescriptorList colDL; |
| 74 | |
| 75 | /** |
| 76 | * Constructor for a ConstraintDescriptor |
| 77 | * |
| 78 | * @param dataDictionary The data dictionary that this descriptor lives in |
| 79 | * @param table The descriptor of the table the constraint is on |
| 80 | * @param constraintName The name of the constraint. |
| 81 | * @param deferrable If the constraint can be deferred. |
| 82 | * @param initiallyDeferred If the constraint starts life deferred. |
| 83 | * @param referencedColumns columns that the constraint references |
| 84 | * @param constraintId UUID of constraint |
| 85 | * @param schemaDesc SchemaDescriptor |
| 86 | */ |
| 87 | |
| 88 | ConstraintDescriptor( |
| 89 | DataDictionary dataDictionary, |
| 90 | TableDescriptor table, |
| 91 | String constraintName, |
| 92 | boolean deferrable, |
| 93 | boolean initiallyDeferred, |
| 94 | int[] referencedColumns, |
| 95 | UUID constraintId, |
| 96 | SchemaDescriptor schemaDesc, |
| 97 | boolean isEnabled |
| 98 | ) |
| 99 | { |
| 100 | super( dataDictionary ); |
| 101 | |
| 102 | this.table = table; |
| 103 | this.constraintName = constraintName; |
| 104 | this.deferrable = deferrable; |
| 105 | this.initiallyDeferred = initiallyDeferred; |
| 106 | this.referencedColumns = referencedColumns; |
| 107 | this.constraintId = constraintId; |
| 108 | this.schemaDesc = schemaDesc; |
| 109 | this.isEnabled = isEnabled; |
| 110 | } |
| 111 | |
| 112 | |
| 113 | /** |
| 114 | * Gets the UUID of the table the constraint is on. |
| 115 | * |
| 116 | * @return The UUID of the table the constraint is on. |
| 117 | */ |
| 118 | public UUID getTableId() |
| 119 | { |
| 120 | return table.getUUID(); |
| 121 | } |
| 122 | |
| 123 | /** |
| 124 | * Sets the UUID of the constraint. |
| 125 | * |
| 126 | * @param constraintId The constraint Id. |
| 127 | */ |
| 128 | public void setConstraintId(UUID constraintId) |
| 129 | { |
| 130 | this.constraintId = constraintId; |
| 131 | } |
| 132 | |
| 133 | /** |
| 134 | * Gets the UUID of the constraint. |
| 135 | * |
| 136 | * @return The UUID of the constraint. |
| 137 | */ |
| 138 | public UUID getUUID() |
| 139 | { |
| 140 | return constraintId; |
| 141 | } |
| 142 | |
| 143 | /** |
| 144 | * Gets the name of the constraint. |
| 145 | * |
| 146 | * @return A String containing the name of the constraint. |
| 147 | */ |
| 148 | public String getConstraintName() |
| 149 | { |
| 150 | return constraintName; |
| 151 | } |
| 152 | |
| 153 | /** |
| 154 | * Gets an identifier telling what type of descriptor it is |
| 155 | * (UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK). |
| 156 | * |
| 157 | * @return An identifier telling what type of descriptor it is |
| 158 | * (UNIQUE, PRIMARY KEY, FOREIGN KEY, CHECK). |
| 159 | */ |
| 160 | public abstract int getConstraintType(); |
| 161 | |
| 162 | public abstract UUID getConglomerateId(); |
| 163 | |
| 164 | /** |
| 165 | * Get the text of the constraint. (Only non-null/meaningful for check |
| 166 | * constraints.) |
| 167 | * @return The constraint text. |
| 168 | */ |
| 169 | public String getConstraintText() |
| 170 | { |
| 171 | return null; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * Returns TRUE if the constraint is deferrable |
| 176 | * (we will probably not do deferrable constraints in the |
| 177 | * initial release, but I want this to be part of the interface). |
| 178 | * |
| 179 | * @return TRUE if the constraint is deferrable, FALSE if not |
| 180 | */ |
| 181 | public boolean deferrable() |
| 182 | { |
| 183 | return deferrable; |
| 184 | } |
| 185 | |
| 186 | /** |
| 187 | * Returns TRUE if the constraint is initially deferred |
| 188 | * (we will probably not do initially deferred constraints |
| 189 | * in the initial release, but I want this to be part of the interface). |
| 190 | * |
| 191 | * @return TRUE if the constraint is initially deferred, |
| 192 | * FALSE if not |
| 193 | */ |
| 194 | public boolean initiallyDeferred() |
| 195 | { |
| 196 | return initiallyDeferred; |
| 197 | } |
| 198 | |
| 199 | /** |
| 200 | * Returns an array of column ids (i.e. ordinal positions) for |
| 201 | * the columns referenced in this table for a primary key, unique |
| 202 | * key, referential, or check constraint. |
| 203 | * |
| 204 | * @return An array of column ids for those constraints that can |
| 205 | * be on columns (primary, unique key, referential |
| 206 | * constraints, and check constraints). For check and |
| 207 | * unique constraints, it returns an array of columns ids |
| 208 | * that are referenced in the constraint. For primary key |
| 209 | * and referential constraints, it returns an array of |
| 210 | * column ids for the columns in this table (i.e. the |
| 211 | * primary key columns for a primary key constraint, |
| 212 | * and the foreign key columns for a foreign key |
| 213 | * constraint. |
| 214 | */ |
| 215 | public int[] getReferencedColumns() |
| 216 | { |
| 217 | return referencedColumns; |
| 218 | } |
| 219 | |
| 220 | /** |
| 221 | * Does this constraint have a backing index? |
| 222 | * |
| 223 | * @return boolean Whether or not there is a backing index for this constraint. |
| 224 | */ |
| 225 | public abstract boolean hasBackingIndex(); |
| 226 | |
| 227 | /** |
| 228 | * Get the SchemaDescriptor for the schema that this constraint |
| 229 | * belongs to. |
| 230 | * |
| 231 | * @return SchemaDescriptor The SchemaDescriptor for this constraint. |
| 232 | */ |
| 233 | public SchemaDescriptor getSchemaDescriptor() |
| 234 | { |
| 235 | return schemaDesc; |
| 236 | } |
| 237 | |
| 238 | /** |
| 239 | RESOLVE: For now the ConstraintDescriptor code stores the array of key |
| 240 | columns in the field 'otherColumns'. Jerry plans to re-organize things. |
| 241 | For now to minimize his rototill I've implemented this function on the |
| 242 | old structures. All new code should use getKeyColumns to get a constraint's |
| 243 | key columns. |
| 244 | |
| 245 | @see org.apache.derby.iapi.sql.dictionary.KeyConstraintDescriptor#getKeyColumns |
| 246 | */ |
| 247 | public int[] getKeyColumns() |
| 248 | { |
| 249 | return getReferencedColumns(); |
| 250 | } |
| 251 | |
| 252 | /** |
| 253 | * Is this constraint active? |
| 254 | * |
| 255 | * @return true/false |
| 256 | */ |
| 257 | public boolean isEnabled() |
| 258 | { |
| 259 | return isEnabled; |
| 260 | } |
| 261 | |
| 262 | /** |
| 263 | * Set the constraint to enabled. |
| 264 | * Does not update the data dictionary |
| 265 | */ |
| 266 | public void setEnabled() |
| 267 | { |
| 268 | isEnabled = true; |
| 269 | } |
| 270 | |
| 271 | /** |
| 272 | * Set the constraint to disabled. |
| 273 | * Does not update the data dictionary |
| 274 | */ |
| 275 | public void setDisabled() |
| 276 | { |
| 277 | isEnabled = false; |
| 278 | } |
| 279 | |
| 280 | /** |
| 281 | * Is this constraint referenced? Return |
| 282 | * false. Overridden by ReferencedKeyConstraints. |
| 283 | * |
| 284 | * @return false |
| 285 | */ |
| 286 | public boolean isReferenced() |
| 287 | { |
| 288 | return false; |
| 289 | } |
| 290 | |
| 291 | /** |
| 292 | * Get the number of enabled fks that |
| 293 | * reference this key. Overriden by |
| 294 | * ReferencedKeyConstraints. |
| 295 | * |
| 296 | * @return the number of fks |
| 297 | */ |
| 298 | public int getReferenceCount() |
| 299 | { |
| 300 | return 0; |
| 301 | } |
| 302 | |
| 303 | /** |
| 304 | * Does this constraint need to fire on this type of |
| 305 | * DML? |
| 306 | * |
| 307 | * @param stmtType the type of DML |
| 308 | * (StatementType.INSERT|StatementType.UPDATE|StatementType.DELETE) |
| 309 | * @param modifiedCols the columns modified, or null for all |
| 310 | * |
| 311 | * @return true/false |
| 312 | */ |
| 313 | public abstract boolean needsToFire(int stmtType, int[] modifiedCols); |
| 314 | |
| 315 | /** |
| 316 | * Get the table descriptor upon which this constraint |
| 317 | * is declared. |
| 318 | * |
| 319 | * @return the table descriptor |
| 320 | */ |
| 321 | public TableDescriptor getTableDescriptor() |
| 322 | { |
| 323 | return table; |
| 324 | } |
| 325 | |
| 326 | /** |
| 327 | * Get the column descriptors for all the columns |
| 328 | * referenced by this constraint. |
| 329 | * |
| 330 | * @return the column descriptor list |
| 331 | * |
| 332 | * @exception StandardException on error |
| 333 | */ |
| 334 | public ColumnDescriptorList getColumnDescriptors() |
| 335 | throws StandardException |
| 336 | { |
| 337 | if (colDL == null) |
| 338 | { |
| 339 | DataDictionary dd = getDataDictionary(); |
| 340 | colDL = new ColumnDescriptorList(); |
| 341 | |
| 342 | int[] refCols = getReferencedColumns(); |
| 343 | for (int i = 0; i < refCols.length; i++) |
| 344 | { |
| 345 | colDL.add(table.getColumnDescriptor(refCols[i])); |
| 346 | } |
| 347 | } |
| 348 | return colDL; |
| 349 | } |
| 350 | |
| 351 | /** |
| 352 | * Indicates whether the column descriptor list is |
| 353 | * type comparable with the constraints columns. The |
| 354 | * types have to be identical AND in the same order |
| 355 | * to succeed. |
| 356 | * |
| 357 | * @param otherColumns the columns to compare |
| 358 | * |
| 359 | * @return true/false |
| 360 | * |
| 361 | * @exception StandardException on error |
| 362 | */ |
| 363 | public boolean areColumnsComparable(ColumnDescriptorList otherColumns) |
| 364 | throws StandardException |
| 365 | { |
| 366 | ColumnDescriptor myColumn; |
| 367 | ColumnDescriptor otherColumn; |
| 368 | |
| 369 | ColumnDescriptorList myColDl = getColumnDescriptors(); |
| 370 | |
| 371 | /* |
| 372 | ** Check the lenghts of the lists |
| 373 | */ |
| 374 | if (otherColumns.size() != myColDl.size()) |
| 375 | { |
| 376 | return false; |
| 377 | } |
| 378 | |
| 379 | int mySize = myColDl.size(); |
| 380 | int otherSize = otherColumns.size(); |
| 381 | int index; |
| 382 | for (index = 0; index < mySize && index < otherSize; index++) |
| 383 | { |
| 384 | myColumn = (ColumnDescriptor) myColDl.elementAt(index); |
| 385 | otherColumn = (ColumnDescriptor) otherColumns.elementAt(index); |
| 386 | |
| 387 | /* |
| 388 | ** Just compare the types. Note that this will |
| 389 | ** say a decimal(x,y) != numeric(x,y) even though |
| 390 | ** it does. |
| 391 | */ |
| 392 | if (!(myColumn.getType()).isExactTypeAndLengthMatch( |
| 393 | (otherColumn.getType()))) |
| 394 | { |
| 395 | break; |
| 396 | } |
| 397 | } |
| 398 | |
| 399 | return (index == mySize && index == otherSize); |
| 400 | } |
| 401 | |
| 402 | /** |
| 403 | * Does a column intersect with our referenced columns |
| 404 | * @param columnArray columns to check |
| 405 | * |
| 406 | * Note-- this is not a static method. |
| 407 | */ |
| 408 | public boolean columnIntersects(int columnArray[]) |
| 409 | { |
| 410 | // call static method. |
| 411 | return doColumnsIntersect(getReferencedColumns(), columnArray); |
| 412 | } |
| 413 | |
| 414 | /** |
| 415 | * Does a column in the input set intersect with |
| 416 | * our referenced columns? |
| 417 | * |
| 418 | * @param otherColumns the columns to compare. If |
| 419 | * null, asssumed to mean all columns |
| 420 | * |
| 421 | * @param referencedColumns the columns referenced by the caller |
| 422 | * |
| 423 | * @return true/false |
| 424 | */ |
| 425 | static boolean doColumnsIntersect(int[] otherColumns, int[] referencedColumns) |
| 426 | { |
| 427 | /* |
| 428 | ** It is assumed that if otherColumns is null, then |
| 429 | ** all other columns are modified. In this case, |
| 430 | ** it is assumed that it intersects with some column |
| 431 | ** of ours, so just return true. |
| 432 | */ |
| 433 | if ((otherColumns == null) || (referencedColumns == null)) |
| 434 | { |
| 435 | return true; |
| 436 | } |
| 437 | |
| 438 | for (int outer = 0; outer < referencedColumns.length; outer++) |
| 439 | { |
| 440 | for (int inner = 0; inner < otherColumns.length; inner++) |
| 441 | { |
| 442 | if (referencedColumns[outer] == otherColumns[inner]) |
| 443 | { |
| 444 | return true; |
| 445 | } |
| 446 | } |
| 447 | } |
| 448 | return false; |
| 449 | } |
| 450 | |
| 451 | /** |
| 452 | * Convert the ColumnDescriptor to a String. |
| 453 | * |
| 454 | * @return A String representation of this ColumnDescriptor |
| 455 | */ |
| 456 | |
| 457 | public String toString() |
| 458 | { |
| 459 | if (SanityManager.DEBUG) |
| 460 | { |
| 461 | String tableDesc = |
| 462 | "table: " + |
| 463 | table.getQualifiedName() + "(" + |
| 464 | table.getUUID()+","+ |
| 465 | table.getTableType()+")"; |
| 466 | |
| 467 | return tableDesc + "\n"+ |
| 468 | "constraintName: " + constraintName + "\n" + |
| 469 | "constraintId: " + constraintId + "\n" + |
| 470 | "deferrable: " + deferrable + "\n" + |
| 471 | "initiallyDeferred: " + initiallyDeferred + "\n" + |
| 472 | "referencedColumns: " + referencedColumns + "\n" + |
| 473 | "schemaDesc: " + schemaDesc + "\n" |
| 474 | ; |
| 475 | } |
| 476 | else |
| 477 | { |
| 478 | return ""; |
| 479 | } |
| 480 | } |
| 481 | |
| 482 | //////////////////////////////////////////////////////////////////// |
| 483 | // |
| 484 | // PROVIDER INTERFACE |
| 485 | // |
| 486 | //////////////////////////////////////////////////////////////////// |
| 487 | |
| 488 | /** |
| 489 | @return the stored form of this provider |
| 490 | |
| 491 | @see Dependable#getDependableFinder |
| 492 | */ |
| 493 | public DependableFinder getDependableFinder() |
| 494 | { |
| 495 | return getDependableFinder(StoredFormatIds.CONSTRAINT_DESCRIPTOR_FINDER_V01_ID); |
| 496 | } |
| 497 | |
| 498 | /** |
| 499 | * Return the name of this Provider. (Useful for errors.) |
| 500 | * |
| 501 | * @return String The name of this provider. |
| 502 | */ |
| 503 | public String getObjectName() |
| 504 | { |
| 505 | return constraintName; |
| 506 | } |
| 507 | |
| 508 | /** |
| 509 | * Get the provider's UUID |
| 510 | * |
| 511 | * @return The provider's UUID |
| 512 | */ |
| 513 | public UUID getObjectID() |
| 514 | { |
| 515 | return constraintId; |
| 516 | } |
| 517 | |
| 518 | /** |
| 519 | * Get the provider's type. |
| 520 | * |
| 521 | * @return char The provider's type. |
| 522 | */ |
| 523 | public String getClassType() |
| 524 | { |
| 525 | return Dependable.CONSTRAINT; |
| 526 | } |
| 527 | |
| 528 | ////////////////////////////////////////////////////// |
| 529 | // |
| 530 | // DEPENDENT INTERFACE |
| 531 | // |
| 532 | ////////////////////////////////////////////////////// |
| 533 | /** |
| 534 | * Check that all of the dependent's dependencies are valid. |
| 535 | * |
| 536 | * @return true if the dependent is currently valid |
| 537 | */ |
| 538 | public synchronized boolean isValid() |
| 539 | { |
| 540 | return true; |
| 541 | } |
| 542 | |
| 543 | /** |
| 544 | * Prepare to mark the dependent as invalid (due to at least one of |
| 545 | * its dependencies being invalid). |
| 546 | * |
| 547 | * @param action The action causing the invalidation |
| 548 | * @param p the provider |
| 549 | * |
| 550 | * @exception StandardException thrown if unable to make it invalid |
| 551 | */ |
| 552 | public void prepareToInvalidate(Provider p, int action, |
| 553 | LanguageConnectionContext lcc) |
| 554 | throws StandardException |
| 555 | { |
| 556 | DependencyManager dm = getDataDictionary().getDependencyManager(); |
| 557 | |
| 558 | switch (action) |
| 559 | { |
| 560 | /* |
| 561 | ** A SET CONSTRAINT stmt will throw an SET_CONSTRAINTS action |
| 562 | ** when enabling/disabling constraints. We'll ignore it. |
| 563 | ** Same for SET TRIGGERS |
| 564 | */ |
| 565 | case DependencyManager.SET_CONSTRAINTS_ENABLE: |
| 566 | case DependencyManager.SET_CONSTRAINTS_DISABLE: |
| 567 | case DependencyManager.SET_TRIGGERS_ENABLE: |
| 568 | case DependencyManager.SET_TRIGGERS_DISABLE: |
| 569 | break; |
| 570 | |
| 571 | /* |
| 572 | ** Currently, the only thing we are depenedent |
| 573 | ** on is another constraint or an alias.. |
| 574 | */ |
| 575 | default: |
| 576 | throw StandardException.newException(SQLState.LANG_PROVIDER_HAS_DEPENDENT_OBJECT, |
| 577 | dm.getActionString(action), |
| 578 | p.getObjectName(), "CONSTRAINT", constraintName); |
| 579 | } |
| 580 | } |
| 581 | |
| 582 | /** |
| 583 | * Mark the dependent as invalid (due to at least one of |
| 584 | * its dependencies being invalid). Always an error |
| 585 | * for a constraint -- should never have gotten here. |
| 586 | * |
| 587 | * @param action The action causing the invalidation |
| 588 | * |
| 589 | * @exception StandardException thrown if called in sanity mode |
| 590 | */ |
| 591 | public void makeInvalid(int action, LanguageConnectionContext lcc) |
| 592 | throws StandardException |
| 593 | { |
| 594 | /* |
| 595 | ** SET_CONSTRAINTS/TRIGGERS is the only valid action |
| 596 | */ |
| 597 | if ((action != DependencyManager.SET_CONSTRAINTS_DISABLE) && |
| 598 | (action != DependencyManager.SET_CONSTRAINTS_ENABLE) && |
| 599 | (action != DependencyManager.SET_TRIGGERS_ENABLE) && |
| 600 | (action != DependencyManager.SET_TRIGGERS_DISABLE) |
| 601 | ) |
| 602 | { |
| 603 | /* |
| 604 | ** We should never get here, we should have barfed on |
| 605 | ** prepareToInvalidate(). |
| 606 | */ |
| 607 | if (SanityManager.DEBUG) |
| 608 | { |
| 609 | DependencyManager dm; |
| 610 | |
| 611 | dm = getDataDictionary().getDependencyManager(); |
| 612 | |
| 613 | SanityManager.THROWASSERT("makeInvalid("+ |
| 614 | dm.getActionString(action)+ |
| 615 | ") not expected to get called"); |
| 616 | } |
| 617 | } |
| 618 | } |
| 619 | |
| 620 | /** |
| 621 | * Attempt to revalidate the dependent. Meaningless |
| 622 | * for constraints. |
| 623 | */ |
| 624 | public void makeValid(LanguageConnectionContext lcc) |
| 625 | { |
| 626 | } |
| 627 | |
| 628 | /** @see TupleDescriptor#getDescriptorName */ |
| 629 | public String getDescriptorName() { return constraintName; } |
| 630 | |
| 631 | public String getDescriptorType() { return "Constraint"; } |
| 632 | } |