fixed SQL parsing from issue examples

Author: chernser

.gitignore

@@ -48,6 +48,8 @@ java.prof
 jmh-result.*
 profile.html
 jdbc-v2/gen
+jdbc-v2/src/main/antlr4/com/clickhouse/jdbc/internal/gen
+
 
 # Shell scripts
 *.sh

client-v2/src/test/java/com/clickhouse/client/ClientTests.java

@@ -296,8 +296,8 @@ public void testWithOldDefaults() {
                 .useHttpCompression(false)
                 .appCompressedData(false)
                 .setSocketTimeout(0, SECONDS)
-                .setSocketRcvbuf(8196)
-                .setSocketSndbuf(8196)
+                .setSocketRcvbuf(804800)
+                .setSocketSndbuf(804800)
                 .build()) {
             Map<String, String> config = client.getConfiguration();
             for (ClientConfigProperties p : ClientConfigProperties.values()) {

jdbc-v2/src/main/antlr4/com/clickhouse/jdbc/internal/ClickHouseParser.g4

@@ -961,6 +961,7 @@ keyword
     | UPDATE
     | USE
     | USING
+    | USER
     | UUID
     | VALUES
     | VIEW

jdbc-v2/src/test/java/com/clickhouse/jdbc/internal/SqlParserTest.java

@@ -298,6 +298,7 @@ public Object[][] testMiscStmtDp() {
             {"insert into `events` (s) values ('a')", 0},
             {"SELECT COUNT(*) > 0 FROM system.databases WHERE name = ?", 1},
             {"SELECT count(*) > 0 FROM system.databases WHERE c1 = ?", 1},
+            {"alter table user delete where reg_time = ?", 1},
         };
     }
 }