Better foreign key handling: correct SQL output

diff --git a/README.md b/README.md
index ef279e6..b57f840 100644 (file)
--- a/README.md
+++ b/README.md
@@ -56,10 +56,11 @@ To indicate an inheritance relation, proceed as follow
        Animal Cat Fish
        Planet Mars Venus
 
-Finally, blocks must be separated by new lines. For a usage example, see example.html (it should render as seen in example\_\*.svg)
+Finally, blocks must be separated by new lines. For a usage example, see example.html (it should render as seen in example\_\*.svg);
+or example2.html for a bigger, more realistic illustration (small social network).
 
 Note that the "drawMcd" method can take a second argument, which indicates the type of graph.
- * "bubble" draws the standard graph, as seen [here](https://en.wikipedia.org/wiki/Entity%E2%80%93relationship_model#/media/File:ER_Diagram_MMORPG.png) for example
+ * "bubble" draws the standard graph, as seen [here](https://en.wikipedia.org/wiki/Entity%E2%80%93relationship_model#/media/File:ER_Diagram_MMORPG.png)
  * "compact" (default) use the same box for an entity and its attributes
 
 -----

diff --git a/example.html b/examples/example.html
similarity index 100%
rename from example.html
rename to examples/example.html

diff --git a/examples/example2.html b/examples/example2.html
new file mode 100644 (file)
index 0000000..9d424c2
--- /dev/null
+++ b/examples/example2.html
@@ -0,0 +1,83 @@
+<h2>MCD graph:</h3>
+<div id="mcd"></div>
+
+<h2>MLD graph:</h2>
+<div id="mld"></div>
+
+<h2>SQL instructions:</h2>
+<div id="sql"></div>
+
+<script src="//cdnjs.cloudflare.com/ajax/libs/underscore.js/1.8.3/underscore-min.js"></script>
+<script src="parser.js"></script>
+<script>
+       let er =
+               new ErDiags(`
+                       [Users]
+                       +id
+                       name VARCHAR NOT NULL
+                       email VARCHAR
+                       location VARCHAR
+                       birthdate DATE
+                       gender CHARACTER
+                       avatar BLOB
+
+                       [Groups]
+                       +id
+                       name VARCHAR NOT NULL
+                       description TEXT
+
+                       [Events]
+                       +id
+                       name VARCHAR NOT NULL
+                       description TEXT
+
+                       [Messages]
+                       +id
+                       date DATE NOT NULL
+                       content TEXT NOT NULL
+                       receiver INTEGER REFERENCES Users(id) NOT NULL
+
+                       [Posts]
+                       +id
+                       content TEXT NOT NULL
+                       date DATE NOT NULL
+                       type VARCHAR NOT NULL DEFAULT "Wall"
+                       reference INTEGER NOT NULL
+
+                       {publish}
+                       Posts 1
+                       Users *
+
+                       {send}
+                       Messages 1
+                       Users *
+
+                       {like}
+                       Users *
+                       Posts *
+
+                       {follow}
+                       Users *
+                       Users *
+
+                       {friend_with}
+                       Users *
+                       Users *
+
+                       {participate}
+                       Events *
+                       Users *
+                       --
+                       degree VARCHAR NOT NULL DEFAULT "sure"
+                       creator BOOLEAN
+
+                       {belong_to}
+                       Groups +
+                       Users *
+                       --
+                                       creator BOOLEAN
+               `);
+       er.drawMcd("mcd"); //,"bubble"
+       er.drawMld("mld");
+       er.fillSql("sql");
+</script>

diff --git a/example_MCD.svg b/examples/example_MCD.svg
similarity index 100%
rename from example_MCD.svg
rename to examples/example_MCD.svg

diff --git a/example_MLD.svg b/examples/example_MLD.svg
similarity index 100%
rename from example_MLD.svg
rename to examples/example_MLD.svg

diff --git a/parser.js b/parser.js
index 65ac9ec..5ef2b3f 100644 (file)
--- a/parser.js
+++ b/parser.js
@@ -172,8 +172,11 @@ class ErDiags
                                        isKey: attr.isKey,
                                        qualifiers: attr.qualifiers,
                                };
-                               if (!!attr.qualifiers && !!attr.qualifiers.match(/foreign/i))
+                               if (!!attr.qualifiers && !!attr.qualifiers.match(/references/i))
+                               {
                                        Object.assign(newField, {ref: attr.qualifiers.match(/references ([^\s]+)/i)[1]});
+                                       attr.qualifiers = attr.qualifiers.replace(/references [^\s]+/, "");
+                               }
                                newTable.push(newField);
                        });
                        this.tables[name] = newTable;
@@ -187,8 +190,8 @@ class ErDiags
                                        name: inh.parent + "_id",
                                        type: this.tables[inh.parent][idx].type,
                                        isKey: true,
-                                       qualifiers: (this.tables[inh.parent][idx].qualifiers || "") + " foreign key references " + inh.parent,
-                                       ref: inh.parent,
+                                       qualifiers: this.tables[inh.parent][idx].qualifiers || "",
+                                       ref: inh.parent + "(" + this.tables[inh.parent][idx].name + ")",
                                });
                        });
                });
@@ -213,8 +216,8 @@ class ErDiags
                                                                        isKey: isKey,
                                                                        name: e2.name + "_" + attr.name,
                                                                        type: attr.type,
-                                                                       qualifiers: "foreign key references " + e2.name + " " + (!isKey && e.card[0]=='1' ? "not null" : ""),
-                                                                       ref: e2.name, //easier drawMld function (fewer regexps)
+                                                                       qualifiers: !isKey && e.card[0]=='1' ? "not null" : "",
+                                                                       ref: e2.name + "(" + attr.name + ")",
                                                                });
                                                        }
                                                });
@@ -243,8 +246,8 @@ class ErDiags
                                                        name: item.entity + "_" + f.name,
                                                        isKey: true,
                                                        type: f.type,
-                                                       qualifiers: (f.qualifiers || "") + " foreign key references " + item.entity,
-                                                       ref: item.entity,
+                                                       qualifiers: f.qualifiers || "",
+                                                       ref: item.entity + "(" + f.name + ")",
                                                });
                                        });
                                });
@@ -447,20 +450,11 @@ class ErDiags
                                mldDot += '<tr><td port="' + f.name + '"' + ' BGCOLOR="#FFFFFF" BORDER="0" ALIGN="LEFT"><font COLOR="#000000" >' + label + '</font></td></tr>\n';
                                if (!!f.ref)
                                {
-                                       // Need to find a key attribute in reference entity (the first...)
-                                       let keyInRef = "";
-                                       for (let field of this.tables[f.ref])
-                                       {
-                                               if (field.isKey)
-                                               {
-                                                       keyInRef = field.name;
-                                                       break;
-                                               }
-                                       }
+                                       const refPort = f.ref.slice(0,-1).replace('(',':');
                                        if (Math.random() < 0.5)
-                                               links += '"' + f.ref + '":"' + keyInRef + '" -- "' + name+'":"'+f.name + '" [dir="forward",arrowhead="dot"';
+                                               links += refPort + ' -- "' + name+'":"'+f.name + '" [dir="forward",arrowhead="dot"';
                                        else
-                                               links += '"'+name+'":"'+f.name+'" -- "' + f.ref + '":"' + keyInRef + '" [dir="back",arrowtail="dot"';
+                                               links += '"'+name+'":"'+f.name+'" -- ' + refPort + ' [dir="back",arrowtail="dot"';
                                        links += ']\n;';
                                }
                        });
@@ -487,14 +481,23 @@ class ErDiags
                Object.keys(this.tables).forEach( name => {
                        sqlText += "CREATE TABLE " + name + " (\n";
                        let key = "";
+                       let foreignKey = [ ];
                        this.tables[name].forEach( f => {
                                let type = f.type || (f.isKey ? "INTEGER" : "TEXT");
+                               if (!!f.ref)
+                                       foreignKey.push({name: f.name, ref: f.ref});
                                sqlText += "\t" + f.name + " " + type + " " + (f.qualifiers || "") + ",\n";
                                if (f.isKey)
                                        key += (key.length>0 ? "," : "") + f.name;
                        });
-                       sqlText += "\tPRIMARY KEY (" + key + ")\n";
-                       sqlText += ");\n";
+                       sqlText += "\tPRIMARY KEY (" + key + ")";
+                       foreignKey.forEach( f => {
+                               let refParts = f.ref.split("(");
+                               const table = refParts[0];
+                               const field = refParts[1].slice(0,-1); //remove last parenthesis
+                               sqlText += ",\n\tFOREIGN KEY (" + f.name + ") REFERENCES " + table + "(" + field + ")";
+                       });
+                       sqlText += "\n);\n";
                });
                //console.log(sqlText);
                this.sqlText = sqlText;