fix(compiler): Improved type inference for concat operator

close #2734

Fixed sqlite engine treating "||" as OR.
MySQL does not have a concat operator, so there is no need to support it.

Author: orisano

internal/compiler/output_columns.go

@@ -163,6 +163,8 @@ func (c *Compiler) outputColumns(qc *QueryCatalog, node ast.Node) ([]*Column, er
 				cols = append(cols, &Column{Name: name, DataType: "bool", NotNull: true})
 			case lang.IsMathematicalOperator(astutils.Join(n.Name, "")):
 				cols = append(cols, &Column{Name: name, DataType: "int", NotNull: true})
+			case astutils.Join(n.Name, "") == "||":
+				cols = append(cols, &Column{Name: name, DataType: "text", NotNull: true})
 			default:
 				cols = append(cols, &Column{Name: name, DataType: "any", NotNull: false})
 			}

internal/compiler/resolve.go

@@ -141,7 +141,7 @@ func (comp *Compiler) resolveCatalogRefs(qc *QueryCatalog, rvs []*ast.RangeVar,
 				// TODO: Move this to database-specific engine package
 				dataType := "any"
 				if astutils.Join(n.Name, ".") == "||" {
-					dataType = "string"
+					dataType = "text"
 				}
 
 				defaultP := named.NewParam("")

internal/endtoend/testdata/concat_operator/postgresql/go/db.go

@@ -0,0 +1,4 @@
+CREATE TABLE foo(bar TEXT, baz TEXT);
+
+-- name: Concat :many
+SELECT bar || ' ' || baz FROM foo;

internal/endtoend/testdata/concat_operator/postgresql/go/models.go

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "engine": "postgresql",
+      "name": "querytest",
+      "schema": "query.sql",
+      "queries": "query.sql"
+    }
+  ]
+}

internal/endtoend/testdata/concat_operator/postgresql/go/query.sql.go

@@ -0,0 +1,4 @@
+CREATE TABLE foo(bar TEXT, baz TEXT);
+
+-- name: Concat :many
+SELECT bar || ' ' || baz FROM foo;

internal/endtoend/testdata/concat_operator/postgresql/query.sql

@@ -0,0 +1,12 @@
+{
+  "version": "1",
+  "packages": [
+    {
+      "path": "go",
+      "engine": "sqlite",
+      "name": "querytest",
+      "schema": "query.sql",
+      "queries": "query.sql"
+    }
+  ]
+}

internal/endtoend/testdata/concat_operator/postgresql/sqlc.json

@@ -768,7 +768,7 @@ func (c *cc) convertMathOperationNode(n *parser.Expr_math_opContext) ast.Node {
 	return &ast.A_Expr{
 		Name: &ast.List{
 			Items: []ast.Node{
-				&ast.String{Str: "+"}, // todo: Convert operation types
+				&ast.String{Str: n.GetChild(1).(antlr.TerminalNode).GetText()}, // todo: Convert operation types
 			},
 		},
 		Lexpr: c.convert(n.Expr(0)),

internal/endtoend/testdata/concat_operator/sqlite/go/db.go

@@ -281,7 +281,7 @@ expr:
     | NAMED_BIND_PARAMETER #expr_bind
     | ((schema_name DOT)? table_name DOT)? column_name #expr_qualified_column_name
     | unary_operator expr #expr_unary
-    | expr PIPE2 expr #expr_binary
+    | expr PIPE2 expr #expr_math_op
     | expr ( STAR | DIV | MOD) expr #expr_math_op
     | expr ( PLUS | MINUS) expr #expr_math_op
     | expr ( LT2 | GT2 | AMP | PIPE) expr #expr_comparison