Migrate install rewriting to new rewriters

2023-11-07 15:26:03 -08:00
parent 3754ae32e4
commit c60d8f90b1
11 changed files with 487 additions and 349 deletions
@@ -0,0 +1,78 @@
+<?php
+
+class DescribeSQLRewriter extends AbstractSQLRewriter
+{
+    public function rewrite(): string
+    {
+        $sql = $this->original();
+        $table = $this->extractTableName($sql);
+        return $this->generatePostgresDescribeTable($table);
+    }
+
+    /**
+     * Extracts table name from a "DESCRIBE" SQL statement.
+     *
+     * @param string $sql The SQL statement
+     * @return string|null The table name if found, or null otherwise
+     */
+    protected function extractTableName($sql) {
+        $pattern = "/DESCRIBE ['\"`]?([^'\"`]+)['\"`]?/i";
+        if (preg_match($pattern, $sql, $matches)) {
+            return $matches[1];
+        }
+        return null;
+    }
+
+    /**
+     * Generates a PostgreSQL-compatible SQL query to mimic MySQL's "DESCRIBE".
+     *
+     * @param string $tableName The table name
+     * @return string The generated SQL query
+     */
+    function generatePostgresDescribeTable($tableName) {
+        $sql = <<<SQL
+            SELECT  
+                f.attnum AS number,  
+                f.attname AS name,  
+                f.attnum,  
+                f.attnotnull AS notnull,  
+                pg_catalog.format_type(f.atttypid,f.atttypmod) AS type,  
+                CASE  
+                    WHEN p.contype = 'p' THEN 't'  
+                    ELSE 'f'  
+                END AS primarykey,  
+                CASE  
+                    WHEN p.contype = 'u' THEN 't'  
+                    ELSE 'f'
+                END AS uniquekey,
+                CASE
+                    WHEN p.contype = 'f' THEN g.relname
+                END AS foreignkey,
+                CASE
+                    WHEN p.contype = 'f' THEN p.confkey
+                END AS foreignkey_fieldnum,
+                CASE
+                    WHEN p.contype = 'f' THEN g.relname
+                END AS foreignkey,
+                CASE
+                    WHEN p.contype = 'f' THEN p.conkey
+                END AS foreignkey_connnum,
+                CASE
+                    WHEN f.atthasdef = 't' THEN pg_get_expr(d.adbin, d.adrelid)
+                END AS default
+            FROM pg_attribute f  
+                JOIN pg_class c ON c.oid = f.attrelid  
+                JOIN pg_type t ON t.oid = f.atttypid  
+                LEFT JOIN pg_attrdef d ON d.adrelid = c.oid AND d.adnum = f.attnum  
+                LEFT JOIN pg_namespace n ON n.oid = c.relnamespace  
+                LEFT JOIN pg_constraint p ON p.conrelid = c.oid AND f.attnum = ANY (p.conkey)  
+                LEFT JOIN pg_class AS g ON p.confrelid = g.oid  
+            WHERE c.relkind = 'r'::char  
+                AND n.nspname = 'public' 
+                AND c.relname = '$tableName'
+                AND f.attnum > 0 ORDER BY number
+        SQL;
+
+        return $sql;
+    }
+}