Oracle query optimization Rewriting techniques and cases, electronics publishing house

1th single-Table query 1
1.1 Querying all rows and columns in a table 1
1.2 Retrieving part of a row from a table 2
1.3 Finding a Null value 3
1.4 Convert null value to actual value 4
1.5 Finding rows that meet multiple criteria 5
1.6 Retrieving part of a column from a table 6
1.7 A meaningful name for the column 6
1.8 Referencing the alias column in the WHERE clause 7
1.9 Stitching Columns 7
1.10 Using conditional logic in a SELECT statement 8
1.11 Limit the number of rows returned 10
1.12 Randomly returning n records from a table 10
1.13 Fuzzy Query 12
2nd. Sort the results of the query 14
2.1 Returning query results in the specified order 14
2.2 Sort by multiple fields 16
2.3 Sort by sub-string 16
2.4 TRANSLATE 17
2.5 Sort letters by numbers and letters in mixed strings 19
2.6 Processing a sort null value 20
2.7 Sorts the values in different columns according to the criteria 21
3rd operation of Multiple tables 23
3.1 UNION all with empty string 23
3.2 Union with or 24
3.3 Group-related rows 31
3.4 In, exists, and inner JOIN 31
3.5 INNER Join, left JOIN, right join, and full join resolution 34
3.6 Self-correlating 37
3.7 Not in, not exists, and left JOIN 38
3.8 Conditions in the outer connection do not put 41
3.9 detect whether the data in two tables and the corresponding data are the same number of bars 45
3.10 Aggregation and internal connection 46
3.11 Aggregation and external connections 50
3.12 Returning lost data from multiple tables 50
Null handling at 3.13 Multi-table Queries 53
Chapter 4th inserting, updating and deleting 55
4.1 Inserting a new record 55
4.2 Block inserting 56 on a few columns
4.3 Definition and data of duplicate tables 57
4.4 Restricting data entry with CHECK option 57
4.5 Multi-Table INSERT statement 58
4.6 Update 62 with values from other tables
4.7 Merging Records 67
4.8 Deleting records that violate referential integrity 70
4.9 Deleting a duplicate name record 71
The 5th chapter uses the string 74
5.1 Traversing a string 74
5.2 string literal contains quotation marks 76
5.3 Count the number of occurrences of a character in a string 77
5.4 Removing unwanted characters from a string 78
5.5 Separating character and digital data 79
5.6 queries that contain only alphanumeric data 80
5.7 capitalized initials of extracted names 85
5.8 Sort by numeric value in string 87
5.9 Create a separate list based on the rows in the table 88
5.10 Extracting the nth delimited substring 88
5.11 Decomposition IP Address 90
5.12 converting delimited data to multivalued in list 90
5.13 sorting strings alphabetically by 91
5.14 distinguishing a string that can be used as a value 94
The 6th chapter uses the number 100
6.1 Common aggregation functions 100
6.2 Build Cumulative and 102
6.3 Calculating the cumulative Difference 106
6.4 Change the cumulative sum of values 108
6.5 Return the top three employees in each department's salary 110
6.6 Calculating the most occurrences of a value of 111
6.7 Returns the row data of the maximum value 113
6.8 First_value 116
6.9 percent of total 119
7th. Date Operation 122
7.1 Plus minus day, month, year 122
7.2 Plus minus hours, minutes, seconds 123
7.3 Time, minute, and second of date interval 124
7.4 Date interval, month, year 124
7.5 Determining the number of working days between two dates 124
7.6 count the number of days in the week of the year 127
7.7 Determine the number of days between the current record and the next record 129
8th. Date Operation 131
8.1 Sysdate can get the information 131
8.2 INTERVAL 134
8.3 EXTRACT 135
8.4 Determining whether a year is a leap 137
8.5 Weeks of calculation 138
8.6 Identify all dates within a year that belong to a day of the week 139
8.7 Determine the first and last "Days of the Week" date in a month 140
8.8 Create this month's calendar 141
8.9 Annual Calendar 142
8.10 Determining start and end dates for a specified year quarter 145
8.11 missing values in the Supplemental range 145
8.12 Find by a given time unit 147
8.13 Special parts of the use date Compare records 148
8.14 Identifying overlapping date ranges 149
8.15 summarize data at specified intervals 152
Chapter 9th Scope of Treatment 155
9.1 Positioning the range of continuous values 155
9.2 Finding the difference between rows in the same group or partition 157
9.3 Positioning the start and end points of a continuous value range 159
9.4 Consolidation time period 164
10th. Advanced Find 168
10.1 Paging The result set 168
10.2 Regenerate Room Number 170
10.3 Skip N rows in table 173
10.4 permutation combination de-weight 174
10.5 Find records containing maximum and minimum values 176
11th Report and Data Warehouse operations 179
11.1 Row to column 179
11.2 Row Career 184
11.3 Reverse the result set to a column 188
11.4 Suppressing duplicate values in the result set 190
11.5 calculation using row to column 191
11.6 Grouping Data 192
11.7 Grouping Data 195
11.8 Calculating a simple subtotal 195
11.9 distinguishing rows of non-subtotals 198
11.10 Subtotal for all expression combinations 201
11.11 distribution of personnel in the work room 203
11.12 Creating a sparse matrix 204
11.13 aggregation at the same time for different groups/partitions 208
11.14 aggregating values for a moving range 209
11.15 Common analysis function Open-window explanation 212
11.16 Listagg and small 99,215
12th Hierarchical Query 217
12.1 Simple tree-shaped query 217
12.2 root node, branch node, leaf node 218
12.3 Sys_connect_by_path 219
12.4 Sorting in a tree query 220
12.5 where 221 in a tree-shaped query
12.6 A branch of the query tree 222
12.7 cut off a branch 223
12.8 field List value de-weight 224
The 13th chapter of the Application case Realization 227
13.1 Extracting elements from a string from a fixed position 227
13.2 Searching for alpha-numeric mixed strings 230
13.3 grading results and converting to columns 230
13.4 Importance of building the underlying data 234
13.5 Returning data from different columns based on incoming criteria 235
13.6 splitting a string to connect 237
13.7 Organizing Junk Data 238
13.8 using "Row to column" To get the hidden information 243
13.9 row to column with hidden data 245
13.10 using regular expressions to extract text-formatted recordsets in CLOB 247
14th Chapter Rewrite the tuning case sharing 249
14.1 Why is it not recommended to use the scalar quantum query 249
14.2 using left JOIN to optimize the scalar subquery 252
14.3 aggregation rewrite of scalar query with left JOIN optimization 252
14.4 Optimizing scalar Quantum queries with left join and row-to-column 255
14.5 scalar in rownum = 1 257
14.6 scalar quantum query for unequal connections overwrite (i) 259
14.7 scalar quantum query for unequal connections rewrite (ii) 262
Consistency of 14.8 scalar quantum query and rewrite logic 267
14.9 Optimizing scalar quantum query with analytic functions (i) 269
14.10 Optimizing scalar quantum queries with analytic functions (II.) 271
14.11 Optimizing scalar quantum queries with analytic functions (iii) 274
14.12 Optimizing scalar quantum queries with analytic functions (iv) 277
14.13 using merge overrides to optimize update 281
14.14 Overwrite update with aggregation operation with merge (i) 283
14.15 Overwrite update with aggregation operation with merge (ii) 286
14.16 multiple subqueries with merge overwrite update (i) 287
14.17 multiple subqueries with merge overwrite update (ii) 288
14.18 Update overwritten with merge issue 291
14.19 Finishing Optimized paging statements 294
14.20 Let the paging statement go right plan 296
14.21 removing distinct from a paged query 297
14.22 reducing self-correlation with a with statement 300
14.23 using with rewrite optimization query 303
14.24 use with to change or to Union 308
14.25 Error with overwrite 312
14.26 Error Analysis function usage 315
14.27 optimizing multiple subqueries with LEFT JOIN (i) 317
14.28 optimizing multiple subqueries with LEFT JOIN (ii) 320
14.29 optimizing multiple subqueries with LEFT JOIN (iii) 322
14.30 removing the filter 324 caused by the exists
14.31 Overlap Time Count 325
14.32 overriding optimizations with analytic functions 328
14.33 parts Suppliers of equal set 334
14.34 Hangar of equal sets with pilot 335
14.35 overriding the maximum filter condition with an analytic function 338
14.36 finding data at a specified level using a tree query 339
14.37 row to column and column career 340
14.38 UPDATE, Row_number, and merge 343
14.39 Rewrite optimization UPDATE statement 345
14.40 overriding the Optimization union ALL statement 347
14.41 Tangled Merge Statement 349
14.42 Remove UNION ALL 351 with case
14.43 inappropriate with and scalar quantum query 364
14.44 Optimizing the scalar quantum query with the analytic function plus "row to column" 366
14.45 dealing with problems with analytic functions 369
14.46 using a row to rewrite a table multi-column association B table same column 372
14.47 overriding the most-valued statement with an analytic function 375
14.48 multi-column associated semi-joins and indexes 377
14.49 skillfully using analytic functions to optimize self-correlation 378
14.50 Tangled UPDATE statement 383
14.51 skillfully merging UNION ALL statements with join conditions 385
14.52 using the analysis function to remove not in 388
14.53 to read the requirements in the query clipping statement 392
14.54 Remove the ingenious of exists in filter 393

Oracle query optimization Rewriting techniques and cases, electronics publishing house