File size: 3,849 Bytes
dc59b01
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
import json
import os
import sqlite3
from datasets import Dataset
from transformers import T5Tokenizer

# =========================================================
# PROJECT ROOT (VERY IMPORTANT — fixes path issues)
# =========================================================
BASE_DIR = os.path.dirname(os.path.dirname(os.path.abspath(__file__)))

TRAIN_JSON = os.path.join(BASE_DIR, "data", "train_spider.json")
DEV_JSON   = os.path.join(BASE_DIR, "data", "dev.json")
DB_FOLDER  = os.path.join(BASE_DIR, "data", "database")

SAVE_TRAIN = os.path.join(BASE_DIR, "data", "tokenized", "train")
SAVE_DEV   = os.path.join(BASE_DIR, "data", "tokenized", "validation")

os.makedirs(os.path.dirname(SAVE_TRAIN), exist_ok=True)

print("Project root:", BASE_DIR)
print("Train file:", TRAIN_JSON)
print("Database folder:", DB_FOLDER)

# =========================================================
# TOKENIZER
# =========================================================
tokenizer = T5Tokenizer.from_pretrained("t5-small")

# =========================================================
# READ DATABASE SCHEMA
# =========================================================
def get_schema(db_path):
    conn = sqlite3.connect(db_path)
    cursor = conn.cursor()

    tables = cursor.execute(
        "SELECT name FROM sqlite_master WHERE type='table';"
    ).fetchall()

    schema_text = []

    for table in tables:
        table = table[0]

        columns = cursor.execute(f"PRAGMA table_info({table});").fetchall()
        col_names = [c[1] for c in columns]

        schema_text.append(f"{table}({', '.join(col_names)})")

    conn.close()
    return "\n".join(schema_text)


# =========================================================
# BUILD TRAINING EXAMPLES
# =========================================================
def build_examples(spider_json):

    print(f"\nBuilding dataset from: {spider_json}")

    data = json.load(open(spider_json))

    inputs = []
    outputs = []

    for ex in data:

        question = ex["question"]
        sql = ex["query"]
        db_id = ex["db_id"]

        db_path = os.path.join(DB_FOLDER, db_id, f"{db_id}.sqlite")

        # skip if db missing (safety)
        if not os.path.exists(db_path):
            continue

        schema = get_schema(db_path)

        # ⭐ SCHEMA-AWARE PROMPT (VERY IMPORTANT)
        input_text = f"""Database Schema:
{schema}

Translate English to SQL:
{question}
SQL:
"""

        inputs.append(input_text)
        outputs.append(sql)

    return Dataset.from_dict({"input": inputs, "output": outputs})


# =========================================================
# TOKENIZE
# =========================================================
def tokenize(example):

    model_input = tokenizer(
        example["input"],
        max_length=512,
        padding="max_length",
        truncation=True
    )

    label = tokenizer(
        example["output"],
        max_length=256,
        padding="max_length",
        truncation=True
    )

    model_input["labels"] = label["input_ids"]
    return model_input


# =========================================================
# RUN PIPELINE
# =========================================================
print("\nBuilding TRAIN dataset...")
train_dataset = build_examples(TRAIN_JSON)

print("Tokenizing TRAIN dataset...")
tokenized_train = train_dataset.map(tokenize, batched=False)

print("Saving TRAIN dataset...")
tokenized_train.save_to_disk(SAVE_TRAIN)


print("\nBuilding VALIDATION dataset...")
val_dataset = build_examples(DEV_JSON)

print("Tokenizing VALIDATION dataset...")
tokenized_val = val_dataset.map(tokenize, batched=False)

print("Saving VALIDATION dataset...")
tokenized_val.save_to_disk(SAVE_DEV)

print("\nDONE ✔ Dataset prepared successfully!")
print("Train saved at:", SAVE_TRAIN)
print("Validation saved at:", SAVE_DEV)