49 lines
2.0 KiB
Plaintext
49 lines
2.0 KiB
Plaintext
DROP TABLE IF EXISTS t1;
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CREATE TABLE t1 (a INT PRIMARY KEY,
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b CHAR(8)
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) ENGINE=xengine;
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SHOW KEYS IN t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Visible Expression
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t1 0 PRIMARY 1 a A # NULL NULL SE_SPECIFIC YES NULL
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INSERT INTO t1 (a,b) VALUES (1,'a'),(2,'b');
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INSERT INTO t1 (a,b) VALUES (1,'c');
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ERROR 23000: Duplicate entry '1' for key 'PRIMARY'
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DROP TABLE t1;
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CREATE TABLE t1 (a INT PRIMARY KEY,
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b CHAR(8) PRIMARY KEY
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) ENGINE=xengine;
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ERROR 42000: Multiple primary key defined
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CREATE TABLE t1 (a INT,
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b CHAR(8),
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PRIMARY KEY (a,b)
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) ENGINE=xengine;
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SHOW INDEX IN t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Visible Expression
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t1 0 PRIMARY 1 a A # NULL NULL SE_SPECIFIC YES NULL
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t1 0 PRIMARY 2 b A # NULL NULL SE_SPECIFIC YES NULL
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INSERT INTO t1 (a,b) VALUES (1,'a'),(1,'b'),(2,'a'),(2,'b');
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INSERT INTO t1 (a,b) VALUES (1,'b');
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ERROR 23000: Duplicate entry '1-b' for key 'PRIMARY'
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DROP TABLE t1;
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CREATE TABLE t1 (a INT KEY,
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b CHAR(8),
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KEY (b)
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) ENGINE=xengine;
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SHOW INDEX IN t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Visible Expression
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t1 0 PRIMARY 1 a A # NULL NULL SE_SPECIFIC YES NULL
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t1 1 b 1 b A # NULL NULL YES SE_SPECIFIC YES NULL
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DROP TABLE t1;
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CREATE TABLE t1 (a INT,
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b CHAR(8) PRIMARY KEY
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) ENGINE=xengine;
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SHOW INDEX IN t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Visible Expression
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t1 0 PRIMARY 1 b A # NULL NULL SE_SPECIFIC YES NULL
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ALTER TABLE t1 ADD CONSTRAINT PRIMARY KEY pk (a);
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ERROR 42000: Multiple primary key defined
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SHOW KEYS IN t1;
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Table Non_unique Key_name Seq_in_index Column_name Collation Cardinality Sub_part Packed Null Index_type Comment Index_comment Visible Expression
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t1 0 PRIMARY 1 b A # NULL NULL SE_SPECIFIC YES NULL
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DROP TABLE t1;
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