Add support for ALTER TABLE ... [DEFAULT] COLLATE [=] collation_name syntax (#2204)

Author: minleejae

src/main/java/net/sf/jsqlparser/statement/alter/AlterExpression.java

@@ -60,6 +60,7 @@ public class AlterExpression implements Serializable {
 
     private String characterSet;
     private String collation;
+    private boolean defaultCollateSpecified;
     private String lockOption;
     private String algorithmOption;
     private String engineOption;
@@ -432,6 +433,14 @@ public void setCollation(String collation) {
         this.collation = collation;
     }
 
+    public void setDefaultCollateSpecified(boolean value) {
+        this.defaultCollateSpecified = value;
+    }
+
+    public boolean isDefaultCollateSpecified() {
+        return defaultCollateSpecified;
+    }
+
     public String getLockOption() {
         return lockOption;
     }
@@ -564,6 +573,17 @@ public String toString() {
                 }
                 b.append(getCollation());
             }
+        } else if (operation == AlterOperation.COLLATE) {
+            if (isDefaultCollateSpecified()) {
+                b.append("DEFAULT ");
+            }
+            b.append("COLLATE ");
+            if (hasEqualForCollate) {
+                b.append("= ");
+            }
+            if (getCollation() != null) {
+                b.append(getCollation());
+            }
         } else if (operation == AlterOperation.DROP_UNIQUE) {
 
             b.append("DROP UNIQUE (").append(PlainSelect.getStringList(pkColumns)).append(')');

src/main/java/net/sf/jsqlparser/statement/alter/AlterOperation.java

@@ -10,7 +10,7 @@
 package net.sf.jsqlparser.statement.alter;
 
 public enum AlterOperation {
-    ADD, ALTER, DROP, DROP_PRIMARY_KEY, DROP_UNIQUE, DROP_FOREIGN_KEY, MODIFY, CHANGE, CONVERT, ALGORITHM, RENAME, RENAME_TABLE, RENAME_INDEX, RENAME_KEY, RENAME_CONSTRAINT, COMMENT, COMMENT_WITH_EQUAL_SIGN, UNSPECIFIC, ADD_PARTITION, DROP_PARTITION, TRUNCATE_PARTITION, SET_TABLE_OPTION, ENGINE, FORCE, LOCK, DISCARD_TABLESPACE, IMPORT_TABLESPACE;
+    ADD, ALTER, DROP, DROP_PRIMARY_KEY, DROP_UNIQUE, DROP_FOREIGN_KEY, MODIFY, CHANGE, CONVERT, COLLATE, ALGORITHM, RENAME, RENAME_TABLE, RENAME_INDEX, RENAME_KEY, RENAME_CONSTRAINT, COMMENT, COMMENT_WITH_EQUAL_SIGN, UNSPECIFIC, ADD_PARTITION, DROP_PARTITION, TRUNCATE_PARTITION, SET_TABLE_OPTION, ENGINE, FORCE, LOCK, DISCARD_TABLESPACE, IMPORT_TABLESPACE;
 
     public static AlterOperation from(String operation) {
         return Enum.valueOf(AlterOperation.class, operation.toUpperCase());

src/main/jjtree/net/sf/jsqlparser/parser/JSqlParserCC.jjt

@@ -8041,14 +8041,28 @@ AlterExpression AlterExpression():
         <K_TO> <K_CHARACTER> <K_SET> tk=<S_IDENTIFIER> { alterExp.setCharacterSet(tk.image); }
         [<K_COLLATE> tk2=<S_IDENTIFIER> { alterExp.setCollation(tk2.image); }]
       )
-      | (<K_DEFAULT> {
-          alterExp.setOperation(AlterOperation.CONVERT);
-          alterExp.setConvertType(AlterExpression.ConvertType.DEFAULT_CHARACTER_SET);
-        }
-        <K_CHARACTER> <K_SET> [ "=" { alterExp.setHasEqualForCharacterSet(true); } ]
-        tk=<S_IDENTIFIER> { alterExp.setCharacterSet(tk.image); }
-        [<K_COLLATE> [ "=" { alterExp.setHasEqualForCollate(true); } ]
-            tk2=<S_IDENTIFIER> { alterExp.setCollation(tk2.image); }]
+      |
+      LOOKAHEAD(3)
+      (
+          <K_DEFAULT>
+          (
+              <K_CHARACTER> <K_SET> [ "=" { alterExp.setHasEqualForCharacterSet(true); } ]
+              tk=<S_IDENTIFIER> {
+                  alterExp.setOperation(AlterOperation.CONVERT);
+                  alterExp.setConvertType(AlterExpression.ConvertType.DEFAULT_CHARACTER_SET);
+                  alterExp.setCharacterSet(tk.image);
+              }
+              [<K_COLLATE> [ "=" { alterExp.setHasEqualForCollate(true); } ]
+                  tk2=<S_IDENTIFIER> { alterExp.setCollation(tk2.image); }]
+          |
+              <K_COLLATE>
+              [ "=" { alterExp.setHasEqualForCollate(true); } ]
+              tk=<S_IDENTIFIER> {
+                  alterExp.setOperation(AlterOperation.COLLATE);
+                  alterExp.setCollation(tk.image);
+                  alterExp.setDefaultCollateSpecified(true);
+              }
+          )
       )
       | (<K_CHARACTER> <K_SET> [ "=" { alterExp.setHasEqualForCharacterSet(true); } ]
         tk=<S_IDENTIFIER> {
@@ -8059,6 +8073,12 @@ AlterExpression AlterExpression():
         [<K_COLLATE> [ "=" { alterExp.setHasEqualForCollate(true); } ]
             tk2=<S_IDENTIFIER> { alterExp.setCollation(tk2.image); }]
       )
+      | (<K_COLLATE> { alterExp.setOperation(AlterOperation.COLLATE); }
+      [ "=" { alterExp.setHasEqualForCollate(true); } ]
+        tk=<S_IDENTIFIER> {
+          alterExp.setCollation(tk.image);
+        }
+      )
       |
       (<K_COMMENT> {alterExp.setOperation(AlterOperation.COMMENT);}
           ["=" {alterExp.setOperation(AlterOperation.COMMENT_WITH_EQUAL_SIGN);} ]

src/test/java/net/sf/jsqlparser/statement/alter/AlterTest.java

@@ -1074,6 +1074,49 @@ public void testIssue2027() throws JSQLParserException {
         assertSqlCanBeParsedAndDeparsed(sqlLongText);
     }
 
+    @Test
+    public void testAlterTableCollate() throws JSQLParserException {
+        // Case 1: Without DEFAULT and without =
+        String sql = "ALTER TABLE tbl_name COLLATE collation_name";
+
+        Alter alter = (Alter) CCJSqlParserUtil.parse(sql);
+        AlterExpression expression = alter.getAlterExpressions().get(0);
+        assertEquals(expression.getOperation(), AlterOperation.COLLATE);
+        assertEquals(expression.getCollation(), "collation_name");
+        assertFalse(expression.isDefaultCollateSpecified());
+        assertSqlCanBeParsedAndDeparsed(sql);
+
+        // Case 2: Without DEFAULT and with =
+        sql = "ALTER TABLE tbl_name COLLATE = collation_name";
+
+        alter = (Alter) CCJSqlParserUtil.parse(sql);
+        expression = alter.getAlterExpressions().get(0);
+        assertEquals(expression.getOperation(), AlterOperation.COLLATE);
+        assertEquals(expression.getCollation(), "collation_name");
+        assertFalse(expression.isDefaultCollateSpecified());
+        assertSqlCanBeParsedAndDeparsed(sql);
+
+        // Case 3: With DEFAULT and without =
+        sql = "ALTER TABLE tbl_name DEFAULT COLLATE collation_name";
+
+        alter = (Alter) CCJSqlParserUtil.parse(sql);
+        expression = alter.getAlterExpressions().get(0);
+        assertEquals(expression.getOperation(), AlterOperation.COLLATE);
+        assertEquals(expression.getCollation(), "collation_name");
+        assertTrue(expression.isDefaultCollateSpecified());
+        assertSqlCanBeParsedAndDeparsed(sql);
+
+        // Case 4: With DEFAULT and with =
+        sql = "ALTER TABLE tbl_name DEFAULT COLLATE = collation_name";
+
+        alter = (Alter) CCJSqlParserUtil.parse(sql);
+        expression = alter.getAlterExpressions().get(0);
+        assertEquals(expression.getOperation(), AlterOperation.COLLATE);
+        assertEquals(expression.getCollation(), "collation_name");
+        assertTrue(expression.isDefaultCollateSpecified());
+        assertSqlCanBeParsedAndDeparsed(sql);
+    }
+
     @Test
     public void testIssue2090LockNone() throws JSQLParserException {
         String sql =