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1
10
11 package com.triactive.jdo.store;
12
13 import java.math.BigInteger  ;
14 import java.sql.Connection ;
15 import java.sql.DatabaseMetaData ;
16 import java.sql.ResultSet ;
17 import java.sql.Statement ;
18 import java.sql.SQLException ;
19 import java.util.ArrayList ;
20 import javax.jdo.JDOFatalDataStoreException;
21
22
23
31
32 class DB2Adapter extends DatabaseAdapter
33 {
34
39
40 protected DB2Adapter(DatabaseMetaData metadata)
41 {
42 super(metadata);
43
44 maxConstraintNameLength = 18;
45 maxIndexNameLength = 18;
46 }
47
48 public String getVendorID()
49 {
50 return "db2";
51 }
52
53 public String getSchemaName(Connection conn) throws SQLException
54 {
55 Statement stmt = conn.createStatement();
56
57 try
58 {
59 String stmtText = "VALUES (CURRENT SCHEMA)";
60 ResultSet rs = stmt.executeQuery(stmtText);
61
62 try
63 {
64 if (!rs.next())
65 throw new JDOFatalDataStoreException("No result returned from " + stmtText);
66
67 return rs.getString(1).trim();
68 }
69 finally
70 {
71 rs.close();
72 }
73 }
74 finally
75 {
76 stmt.close();
77 }
78 }
79
80 public boolean supportsBooleanComparison()
81 {
82 return false;
83 }
84
85 public boolean supportsDeferredConstraints()
86 {
87 return false;
88 }
89
90 public boolean supportsNullsInCandidateKeys()
91 {
92 return false;
93 }
94
95 public ColumnInfo newColumnInfo(ResultSet rs)
96 {
97 return new DB2ColumnInfo(rs);
98 }
99
100 public TableExpression newTableExpression(QueryStatement qs, Table table, SQLIdentifier rangeVar)
101 {
102 return new TableExprAsSubquery(qs, table, rangeVar);
103 }
104
105 public int getUnlimitedLengthPrecisionValue(TypeInfo typeInfo)
106 {
107 if (typeInfo.dataType == java.sql.Types.BLOB || typeInfo.dataType == java.sql.Types.CLOB)
108 return 1 << 30;
109 else
110 return super.getUnlimitedLengthPrecisionValue(typeInfo);
111 }
112
113 public String getDropTableStatement(BaseTable table)
114 {
115 return "DROP TABLE " + table.getName();
116 }
117
118 public NumericExpression lengthMethod(CharacterExpression str)
119 {
120 ArrayList args = new ArrayList ();
121 args.add(str);
122
123 return new NumericExpression("LENGTH", args);
124 }
125
126 public CharacterExpression substringMethod(CharacterExpression str,
127 NumericExpression begin)
128 {
129 ArrayList args = new ArrayList ();
130 args.add(str);
131 args.add(begin.add(new IntegerLiteral(str.getQueryStatement(), BigInteger.ONE)));
132
133 return new CharacterExpression("SUBSTR", args);
134 }
135
136 public CharacterExpression substringMethod(CharacterExpression str,
137 NumericExpression begin,
138 NumericExpression end)
139 {
140 ArrayList args = new ArrayList ();
141 args.add(str);
142 args.add(begin.add(new IntegerLiteral(str.getQueryStatement(), BigInteger.ONE)));
143 args.add(end.sub(begin));
144
145 return new CharacterExpression("SUBSTR", args);
146 }
147 }
148 |
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