sql: allow to specify engine in CREATE TABLE stmt

Closes #4422

@TarantoolBot document
Title: Introduce <WITH ENGINE> clause for CREATE TABLE statement

To allow user to specify engine as per table option, CREATE TABLE
statement has been extended with optional <WITH ENGINE = engine_name>
clause. This clause comes at the end of CREATE TABLE statement.
For instance:

CREATE TABLE t_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'vinyl';

Name of engine is considered to be string literal ergo should be
enclosed in single quotation marks and be lower-cased. Note that engine
specified in WITH ENGINE clause overwrites default engine, which is set
via 'pragma sql_default_engine'.

extra/mkkeywordhash.c

@@ -93,6 +93,7 @@ static Keyword aKeywordTable[] = {
   { "DISTINCT",               "TK_DISTINCT",    true  },
   { "DROP",                   "TK_DROP",        true  },
   { "END",                    "TK_END",         true  },
+  { "ENGINE",                 "TK_ENGINE",      true  },
   { "EACH",                   "TK_EACH",        true  },
   { "ELSE",                   "TK_ELSE",        true  },
   { "ESCAPE",                 "TK_ESCAPE",      true  },

src/box/sql/parse.y

@@ -177,7 +177,7 @@ cmd ::= ROLLBACK TO savepoint_opt nm(X). {
 
 ///////////////////// The CREATE TABLE statement ////////////////////////////
 //
-cmd ::= create_table create_table_args.
+cmd ::= create_table create_table_args with_opts create_table_end.
 create_table ::= createkw TABLE ifnotexists(E) nm(Y). {
   create_table_def_init(&pParse->create_table_def, &Y, E);
   pParse->create_table_def.new_space = sqlStartTable(pParse, &Y);
@@ -189,10 +189,31 @@ createkw(A) ::= CREATE(A).  {disableLookaside(pParse);}
 ifnotexists(A) ::= .              {A = 0;}
 ifnotexists(A) ::= IF NOT EXISTS. {A = 1;}
 
-create_table_args ::= LP columnlist RP. {
-  sqlEndTable(pParse);
+create_table_args ::= LP columnlist RP.
+
+with_opts ::= WITH engine_opts.
+with_opts ::= .
+
+engine_opts ::= ENGINE EQ STRING(A). {
+  /* Note that specifying engine clause overwrites default engine. */
+  if (A.n > ENGINE_NAME_MAX) {
+    diag_set(ClientError, ER_CREATE_SPACE,
+             pParse->create_table_def.new_space->def->name,
+             "space engine name is too long");
+    pParse->is_aborted = true;
+    return;
+  }
+  /* Need to dequote name. */
+  char *normalized_name = sql_name_from_token(pParse->db, &A);
+  if (normalized_name == NULL)
+    return;
+  memcpy(pParse->create_table_def.new_space->def->engine_name, normalized_name,
+         strlen(normalized_name) + 1);
+  sqlDbFree(pParse->db, normalized_name);
 }
 
+create_table_end ::= . { sqlEndTable(pParse); }
+
 /*
  * CREATE TABLE AS SELECT is broken. To be re-implemented
  * in gh-3223.

test/sql/engine.result

@@ -48,3 +48,88 @@ box.execute("DROP TABLE t3_memtx;")
 ---
 - row_count: 1
 ...
+-- gh-4422: allow to specify engine in CREATE TABLE statement.
+--
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'vinyl'")
+---
+- row_count: 1
+...
+assert(box.space.T1_VINYL.engine == 'vinyl')
+---
+- true
+...
+box.execute("CREATE TABLE t1_memtx (id INT PRIMARY KEY) WITH ENGINE = 'memtx'")
+---
+- row_count: 1
+...
+assert(box.space.T1_MEMTX.engine == 'memtx')
+---
+- true
+...
+box.execute("pragma sql_default_engine='vinyl'")
+---
+- row_count: 0
+...
+box.execute("CREATE TABLE t2_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'vinyl'")
+---
+- row_count: 1
+...
+assert(box.space.T2_VINYL.engine == 'vinyl')
+---
+- true
+...
+box.execute("CREATE TABLE t2_memtx (id INT PRIMARY KEY) WITH ENGINE = 'memtx'")
+---
+- row_count: 1
+...
+assert(box.space.T2_MEMTX.engine == 'memtx')
+---
+- true
+...
+box.space.T1_VINYL:drop()
+---
+...
+box.space.T1_MEMTX:drop()
+---
+...
+box.space.T2_VINYL:drop()
+---
+...
+box.space.T2_MEMTX:drop()
+---
+...
+-- Name of engine considered to be string literal, so should be
+-- lowercased and quoted.
+--
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = VINYL")
+---
+- null
+- Syntax error near 'VINYL'
+...
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = vinyl")
+---
+- null
+- Syntax error near 'vinyl'
+...
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'VINYL'")
+---
+- null
+- Space engine 'VINYL' does not exist
+...
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = \"vinyl\"")
+---
+- null
+- Syntax error near '"vinyl"'
+...
+-- Make sure that wrong engine name is handled properly.
+--
+box.execute("CREATE TABLE t_wrong_engine (id INT PRIMARY KEY) WITH ENGINE = 'abc'")
+---
+- null
+- Space engine 'abc' does not exist
+...
+box.execute("CREATE TABLE t_long_engine_name (id INT PRIMARY KEY) WITH ENGINE = 'very_long_engine_name'")
+---
+- null
+- 'Failed to create space ''T_LONG_ENGINE_NAME'': space engine name is too long'
+...

test/sql/engine.test.lua

@@ -15,3 +15,33 @@ assert(box.space.T3_MEMTX.engine == 'memtx')
 box.execute("DROP TABLE t1_vinyl;")
 box.execute("DROP TABLE t2_vinyl;")
 box.execute("DROP TABLE t3_memtx;")
+
+-- gh-4422: allow to specify engine in CREATE TABLE statement.
+--
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'vinyl'")
+assert(box.space.T1_VINYL.engine == 'vinyl')
+box.execute("CREATE TABLE t1_memtx (id INT PRIMARY KEY) WITH ENGINE = 'memtx'")
+assert(box.space.T1_MEMTX.engine == 'memtx')
+box.execute("pragma sql_default_engine='vinyl'")
+box.execute("CREATE TABLE t2_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'vinyl'")
+assert(box.space.T2_VINYL.engine == 'vinyl')
+box.execute("CREATE TABLE t2_memtx (id INT PRIMARY KEY) WITH ENGINE = 'memtx'")
+assert(box.space.T2_MEMTX.engine == 'memtx')
+
+box.space.T1_VINYL:drop()
+box.space.T1_MEMTX:drop()
+box.space.T2_VINYL:drop()
+box.space.T2_MEMTX:drop()
+
+-- Name of engine considered to be string literal, so should be
+-- lowercased and quoted.
+--
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = VINYL")
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = vinyl")
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = 'VINYL'")
+box.execute("CREATE TABLE t1_vinyl (id INT PRIMARY KEY) WITH ENGINE = \"vinyl\"")
+
+-- Make sure that wrong engine name is handled properly.
+--
+box.execute("CREATE TABLE t_wrong_engine (id INT PRIMARY KEY) WITH ENGINE = 'abc'")
+box.execute("CREATE TABLE t_long_engine_name (id INT PRIMARY KEY) WITH ENGINE = 'very_long_engine_name'")